Index: Python/ceval.c
===================================================================
--- Python/ceval.c	(revision 42536)
+++ Python/ceval.c	(working copy)
@@ -998,6 +998,21 @@
 				SET_SECOND(w);
 				SET_THIRD(v);
 				goto fast_next_opcode;
+			} else if (oparg == 4) {
+				x = TOP();
+				Py_INCREF(x);
+				w = SECOND();
+				Py_INCREF(w);
+				v = THIRD();
+				Py_INCREF(v);
+				u = FOURTH();
+				Py_INCREF(u);
+				STACKADJ(4);
+				SET_TOP(x);
+				SET_SECOND(w);
+				SET_THIRD(v);
+				SET_FOURTH(u);
+				goto fast_next_opcode;
 			}
 			Py_FatalError("invalid argument to DUP_TOPX"
 				      " (bytecode corruption?)");
@@ -4359,3 +4374,4 @@
 }
 
 #endif
+
Index: Python/graminit.c
===================================================================
--- Python/graminit.c	(revision 42536)
+++ Python/graminit.c	(working copy)
@@ -688,23 +688,24 @@
 	{1, arcs_34_3},
 	{1, arcs_34_4},
 };
-static arc arcs_35_0[6] = {
+static arc arcs_35_0[7] = {
 	{84, 1},
 	{85, 1},
 	{86, 1},
 	{87, 1},
+	{88, 1},
 	{17, 1},
-	{88, 1},
+	{89, 1},
 };
 static arc arcs_35_1[1] = {
 	{0, 1},
 };
 static state states_35[2] = {
-	{6, arcs_35_0},
+	{7, arcs_35_0},
 	{1, arcs_35_1},
 };
 static arc arcs_36_0[1] = {
-	{89, 1},
+	{90, 1},
 };
 static arc arcs_36_1[1] = {
 	{26, 2},
@@ -716,8 +717,8 @@
 	{22, 4},
 };
 static arc arcs_36_4[3] = {
-	{90, 1},
-	{91, 5},
+	{91, 1},
+	{92, 5},
 	{0, 4},
 };
 static arc arcs_36_5[1] = {
@@ -740,7 +741,7 @@
 	{1, arcs_36_7},
 };
 static arc arcs_37_0[1] = {
-	{92, 1},
+	{93, 1},
 };
 static arc arcs_37_1[1] = {
 	{26, 2},
@@ -752,7 +753,7 @@
 	{22, 4},
 };
 static arc arcs_37_4[2] = {
-	{91, 5},
+	{92, 5},
 	{0, 4},
 };
 static arc arcs_37_5[1] = {
@@ -775,7 +776,7 @@
 	{1, arcs_37_7},
 };
 static arc arcs_38_0[1] = {
-	{93, 1},
+	{94, 1},
 };
 static arc arcs_38_1[1] = {
 	{59, 2},
@@ -793,7 +794,7 @@
 	{22, 6},
 };
 static arc arcs_38_6[2] = {
-	{91, 7},
+	{92, 7},
 	{0, 6},
 };
 static arc arcs_38_7[1] = {
@@ -818,7 +819,7 @@
 	{1, arcs_38_9},
 };
 static arc arcs_39_0[1] = {
-	{94, 1},
+	{95, 1},
 };
 static arc arcs_39_1[1] = {
 	{21, 2},
@@ -827,8 +828,8 @@
 	{22, 3},
 };
 static arc arcs_39_3[2] = {
-	{95, 4},
-	{96, 5},
+	{96, 4},
+	{97, 5},
 };
 static arc arcs_39_4[1] = {
 	{21, 6},
@@ -843,9 +844,9 @@
 	{22, 9},
 };
 static arc arcs_39_8[4] = {
-	{95, 4},
-	{91, 10},
-	{96, 5},
+	{96, 4},
+	{92, 10},
+	{97, 5},
 	{0, 8},
 };
 static arc arcs_39_9[1] = {
@@ -858,7 +859,7 @@
 	{22, 12},
 };
 static arc arcs_39_12[2] = {
-	{96, 5},
+	{97, 5},
 	{0, 12},
 };
 static state states_39[13] = {
@@ -877,101 +878,126 @@
 	{2, arcs_39_12},
 };
 static arc arcs_40_0[1] = {
-	{97, 1},
+	{98, 1},
 };
-static arc arcs_40_1[2] = {
+static arc arcs_40_1[1] = {
 	{26, 2},
-	{0, 1},
 };
 static arc arcs_40_2[2] = {
-	{27, 3},
-	{0, 2},
+	{99, 3},
+	{21, 4},
 };
 static arc arcs_40_3[1] = {
-	{26, 4},
+	{21, 4},
 };
 static arc arcs_40_4[1] = {
-	{0, 4},
+	{22, 5},
 };
-static state states_40[5] = {
+static arc arcs_40_5[1] = {
+	{0, 5},
+};
+static state states_40[6] = {
 	{1, arcs_40_0},
-	{2, arcs_40_1},
+	{1, arcs_40_1},
 	{2, arcs_40_2},
 	{1, arcs_40_3},
 	{1, arcs_40_4},
+	{1, arcs_40_5},
 };
-static arc arcs_41_0[2] = {
-	{3, 1},
-	{2, 2},
+static arc arcs_41_0[1] = {
+	{19, 1},
 };
-static arc arcs_41_1[1] = {
-	{0, 1},
+static arc arcs_41_1[2] = {
+	{12, 2},
+	{13, 3},
 };
 static arc arcs_41_2[1] = {
-	{98, 3},
+	{0, 2},
 };
 static arc arcs_41_3[1] = {
-	{6, 4},
+	{12, 4},
 };
 static arc arcs_41_4[2] = {
-	{6, 4},
-	{99, 1},
+	{27, 3},
+	{15, 2},
 };
 static state states_41[5] = {
-	{2, arcs_41_0},
-	{1, arcs_41_1},
+	{1, arcs_41_0},
+	{2, arcs_41_1},
 	{1, arcs_41_2},
 	{1, arcs_41_3},
 	{2, arcs_41_4},
 };
-static arc arcs_42_0[2] = {
+static arc arcs_42_0[1] = {
 	{100, 1},
-	{102, 2},
 };
 static arc arcs_42_1[2] = {
-	{101, 3},
+	{26, 2},
 	{0, 1},
 };
-static arc arcs_42_2[1] = {
+static arc arcs_42_2[2] = {
+	{27, 3},
 	{0, 2},
 };
 static arc arcs_42_3[1] = {
-	{100, 1},
+	{26, 4},
 };
-static state states_42[4] = {
-	{2, arcs_42_0},
+static arc arcs_42_4[1] = {
+	{0, 4},
+};
+static state states_42[5] = {
+	{1, arcs_42_0},
 	{2, arcs_42_1},
-	{1, arcs_42_2},
+	{2, arcs_42_2},
 	{1, arcs_42_3},
+	{1, arcs_42_4},
 };
-static arc arcs_43_0[1] = {
-	{103, 1},
+static arc arcs_43_0[2] = {
+	{3, 1},
+	{2, 2},
 };
-static arc arcs_43_1[2] = {
-	{104, 0},
+static arc arcs_43_1[1] = {
 	{0, 1},
 };
-static state states_43[2] = {
-	{1, arcs_43_0},
-	{2, arcs_43_1},
+static arc arcs_43_2[1] = {
+	{101, 3},
 };
+static arc arcs_43_3[1] = {
+	{6, 4},
+};
+static arc arcs_43_4[2] = {
+	{6, 4},
+	{102, 1},
+};
+static state states_43[5] = {
+	{2, arcs_43_0},
+	{1, arcs_43_1},
+	{1, arcs_43_2},
+	{1, arcs_43_3},
+	{2, arcs_43_4},
+};
 static arc arcs_44_0[2] = {
-	{105, 1},
-	{106, 2},
+	{103, 1},
+	{105, 2},
 };
-static arc arcs_44_1[1] = {
-	{103, 2},
+static arc arcs_44_1[2] = {
+	{104, 3},
+	{0, 1},
 };
 static arc arcs_44_2[1] = {
 	{0, 2},
 };
-static state states_44[3] = {
+static arc arcs_44_3[1] = {
+	{103, 1},
+};
+static state states_44[4] = {
 	{2, arcs_44_0},
-	{1, arcs_44_1},
+	{2, arcs_44_1},
 	{1, arcs_44_2},
+	{1, arcs_44_3},
 };
 static arc arcs_45_0[1] = {
-	{81, 1},
+	{106, 1},
 };
 static arc arcs_45_1[2] = {
 	{107, 0},
@@ -981,61 +1007,65 @@
 	{1, arcs_45_0},
 	{2, arcs_45_1},
 };
-static arc arcs_46_0[10] = {
+static arc arcs_46_0[2] = {
 	{108, 1},
-	{109, 1},
-	{110, 1},
-	{111, 1},
-	{112, 1},
-	{113, 1},
-	{114, 1},
-	{82, 1},
-	{105, 2},
-	{115, 3},
+	{109, 2},
 };
 static arc arcs_46_1[1] = {
-	{0, 1},
+	{106, 2},
 };
 static arc arcs_46_2[1] = {
-	{82, 1},
+	{0, 2},
 };
-static arc arcs_46_3[2] = {
-	{105, 1},
-	{0, 3},
-};
-static state states_46[4] = {
-	{10, arcs_46_0},
+static state states_46[3] = {
+	{2, arcs_46_0},
 	{1, arcs_46_1},
 	{1, arcs_46_2},
-	{2, arcs_46_3},
 };
 static arc arcs_47_0[1] = {
-	{116, 1},
+	{81, 1},
 };
 static arc arcs_47_1[2] = {
-	{117, 0},
+	{110, 0},
 	{0, 1},
 };
 static state states_47[2] = {
 	{1, arcs_47_0},
 	{2, arcs_47_1},
 };
-static arc arcs_48_0[1] = {
-	{118, 1},
+static arc arcs_48_0[10] = {
+	{111, 1},
+	{112, 1},
+	{113, 1},
+	{114, 1},
+	{115, 1},
+	{116, 1},
+	{117, 1},
+	{82, 1},
+	{108, 2},
+	{118, 3},
 };
-static arc arcs_48_1[2] = {
-	{119, 0},
+static arc arcs_48_1[1] = {
 	{0, 1},
 };
-static state states_48[2] = {
-	{1, arcs_48_0},
-	{2, arcs_48_1},
+static arc arcs_48_2[1] = {
+	{82, 1},
 };
+static arc arcs_48_3[2] = {
+	{108, 1},
+	{0, 3},
+};
+static state states_48[4] = {
+	{10, arcs_48_0},
+	{1, arcs_48_1},
+	{1, arcs_48_2},
+	{2, arcs_48_3},
+};
 static arc arcs_49_0[1] = {
-	{120, 1},
+	{119, 1},
 };
 static arc arcs_49_1[2] = {
-	{121, 0},
+	{120, 0},
 	{0, 1},
 };
 static state states_49[2] = {
@@ -1043,660 +1073,682 @@
 	{2, arcs_49_1},
 };
 static arc arcs_50_0[1] = {
-	{122, 1},
+	{121, 1},
 };
-static arc arcs_50_1[3] = {
-	{123, 0},
-	{57, 0},
+static arc arcs_50_1[2] = {
+	{122, 0},
 	{0, 1},
 };
 static state states_50[2] = {
 	{1, arcs_50_0},
-	{3, arcs_50_1},
+	{2, arcs_50_1},
 };
 static arc arcs_51_0[1] = {
-	{124, 1},
+	{123, 1},
 };
-static arc arcs_51_1[3] = {
-	{125, 0},
-	{126, 0},
+static arc arcs_51_1[2] = {
+	{124, 0},
 	{0, 1},
 };
 static state states_51[2] = {
 	{1, arcs_51_0},
-	{3, arcs_51_1},
+	{2, arcs_51_1},
 };
 static arc arcs_52_0[1] = {
+	{125, 1},
+};
+static arc arcs_52_1[3] = {
+	{126, 0},
+	{57, 0},
+	{0, 1},
+};
+static state states_52[2] = {
+	{1, arcs_52_0},
+	{3, arcs_52_1},
+};
+static arc arcs_53_0[1] = {
 	{127, 1},
 };
-static arc arcs_52_1[5] = {
-	{28, 0},
+static arc arcs_53_1[3] = {
 	{128, 0},
 	{129, 0},
-	{130, 0},
 	{0, 1},
 };
-static state states_52[2] = {
-	{1, arcs_52_0},
-	{5, arcs_52_1},
+static state states_53[2] = {
+	{1, arcs_53_0},
+	{3, arcs_53_1},
 };
-static arc arcs_53_0[4] = {
-	{125, 1},
-	{126, 1},
-	{131, 1},
-	{132, 2},
+static arc arcs_54_0[1] = {
+	{130, 1},
 };
-static arc arcs_53_1[1] = {
-	{127, 2},
+static arc arcs_54_1[5] = {
+	{28, 0},
+	{131, 0},
+	{132, 0},
+	{133, 0},
+	{0, 1},
 };
-static arc arcs_53_2[1] = {
+static state states_54[2] = {
+	{1, arcs_54_0},
+	{5, arcs_54_1},
+};
+static arc arcs_55_0[4] = {
+	{128, 1},
+	{129, 1},
+	{134, 1},
+	{135, 2},
+};
+static arc arcs_55_1[1] = {
+	{130, 2},
+};
+static arc arcs_55_2[1] = {
 	{0, 2},
 };
-static state states_53[3] = {
-	{4, arcs_53_0},
-	{1, arcs_53_1},
-	{1, arcs_53_2},
+static state states_55[3] = {
+	{4, arcs_55_0},
+	{1, arcs_55_1},
+	{1, arcs_55_2},
 };
-static arc arcs_54_0[1] = {
-	{133, 1},
+static arc arcs_56_0[1] = {
+	{136, 1},
 };
-static arc arcs_54_1[3] = {
-	{134, 1},
+static arc arcs_56_1[3] = {
+	{137, 1},
 	{29, 2},
 	{0, 1},
 };
-static arc arcs_54_2[1] = {
-	{127, 3},
+static arc arcs_56_2[1] = {
+	{130, 3},
 };
-static arc arcs_54_3[1] = {
+static arc arcs_56_3[1] = {
 	{0, 3},
 };
-static state states_54[4] = {
-	{1, arcs_54_0},
-	{3, arcs_54_1},
-	{1, arcs_54_2},
-	{1, arcs_54_3},
+static state states_56[4] = {
+	{1, arcs_56_0},
+	{3, arcs_56_1},
+	{1, arcs_56_2},
+	{1, arcs_56_3},
 };
-static arc arcs_55_0[7] = {
+static arc arcs_57_0[7] = {
 	{13, 1},
-	{136, 2},
-	{139, 3},
-	{142, 4},
+	{139, 2},
+	{142, 3},
+	{145, 4},
 	{19, 5},
-	{144, 5},
-	{145, 6},
+	{147, 5},
+	{148, 6},
 };
-static arc arcs_55_1[3] = {
+static arc arcs_57_1[3] = {
 	{43, 7},
-	{135, 7},
+	{138, 7},
 	{15, 5},
 };
-static arc arcs_55_2[2] = {
-	{137, 8},
-	{138, 5},
-};
-static arc arcs_55_3[2] = {
-	{140, 9},
+static arc arcs_57_2[2] = {
+	{140, 8},
 	{141, 5},
 };
-static arc arcs_55_4[1] = {
-	{143, 10},
+static arc arcs_57_3[2] = {
+	{143, 9},
+	{144, 5},
 };
-static arc arcs_55_5[1] = {
+static arc arcs_57_4[1] = {
+	{146, 10},
+};
+static arc arcs_57_5[1] = {
 	{0, 5},
 };
-static arc arcs_55_6[2] = {
-	{145, 6},
+static arc arcs_57_6[2] = {
+	{148, 6},
 	{0, 6},
 };
-static arc arcs_55_7[1] = {
+static arc arcs_57_7[1] = {
 	{15, 5},
 };
-static arc arcs_55_8[1] = {
-	{138, 5},
-};
-static arc arcs_55_9[1] = {
+static arc arcs_57_8[1] = {
 	{141, 5},
 };
-static arc arcs_55_10[1] = {
-	{142, 5},
+static arc arcs_57_9[1] = {
+	{144, 5},
 };
-static state states_55[11] = {
-	{7, arcs_55_0},
-	{3, arcs_55_1},
-	{2, arcs_55_2},
-	{2, arcs_55_3},
-	{1, arcs_55_4},
-	{1, arcs_55_5},
-	{2, arcs_55_6},
-	{1, arcs_55_7},
-	{1, arcs_55_8},
-	{1, arcs_55_9},
-	{1, arcs_55_10},
+static arc arcs_57_10[1] = {
+	{145, 5},
 };
-static arc arcs_56_0[1] = {
+static state states_57[11] = {
+	{7, arcs_57_0},
+	{3, arcs_57_1},
+	{2, arcs_57_2},
+	{2, arcs_57_3},
+	{1, arcs_57_4},
+	{1, arcs_57_5},
+	{2, arcs_57_6},
+	{1, arcs_57_7},
+	{1, arcs_57_8},
+	{1, arcs_57_9},
+	{1, arcs_57_10},
+};
+static arc arcs_58_0[1] = {
 	{26, 1},
 };
-static arc arcs_56_1[3] = {
-	{146, 2},
+static arc arcs_58_1[3] = {
+	{149, 2},
 	{27, 3},
 	{0, 1},
 };
-static arc arcs_56_2[1] = {
+static arc arcs_58_2[1] = {
 	{0, 2},
 };
-static arc arcs_56_3[2] = {
+static arc arcs_58_3[2] = {
 	{26, 4},
 	{0, 3},
 };
-static arc arcs_56_4[2] = {
+static arc arcs_58_4[2] = {
 	{27, 3},
 	{0, 4},
 };
-static state states_56[5] = {
-	{1, arcs_56_0},
-	{3, arcs_56_1},
-	{1, arcs_56_2},
-	{2, arcs_56_3},
-	{2, arcs_56_4},
+static state states_58[5] = {
+	{1, arcs_58_0},
+	{3, arcs_58_1},
+	{1, arcs_58_2},
+	{2, arcs_58_3},
+	{2, arcs_58_4},
 };
-static arc arcs_57_0[1] = {
+static arc arcs_59_0[1] = {
 	{26, 1},
 };
-static arc arcs_57_1[3] = {
-	{147, 2},
+static arc arcs_59_1[3] = {
+	{150, 2},
 	{27, 3},
 	{0, 1},
 };
-static arc arcs_57_2[1] = {
+static arc arcs_59_2[1] = {
 	{0, 2},
 };
-static arc arcs_57_3[2] = {
+static arc arcs_59_3[2] = {
 	{26, 4},
 	{0, 3},
 };
-static arc arcs_57_4[2] = {
+static arc arcs_59_4[2] = {
 	{27, 3},
 	{0, 4},
 };
-static state states_57[5] = {
-	{1, arcs_57_0},
-	{3, arcs_57_1},
-	{1, arcs_57_2},
-	{2, arcs_57_3},
-	{2, arcs_57_4},
+static state states_59[5] = {
+	{1, arcs_59_0},
+	{3, arcs_59_1},
+	{1, arcs_59_2},
+	{2, arcs_59_3},
+	{2, arcs_59_4},
 };
-static arc arcs_58_0[1] = {
-	{148, 1},
+static arc arcs_60_0[1] = {
+	{151, 1},
 };
-static arc arcs_58_1[2] = {
+static arc arcs_60_1[2] = {
 	{23, 2},
 	{21, 3},
 };
-static arc arcs_58_2[1] = {
+static arc arcs_60_2[1] = {
 	{21, 3},
 };
-static arc arcs_58_3[1] = {
+static arc arcs_60_3[1] = {
 	{26, 4},
 };
-static arc arcs_58_4[1] = {
+static arc arcs_60_4[1] = {
 	{0, 4},
 };
-static state states_58[5] = {
-	{1, arcs_58_0},
-	{2, arcs_58_1},
-	{1, arcs_58_2},
-	{1, arcs_58_3},
-	{1, arcs_58_4},
+static state states_60[5] = {
+	{1, arcs_60_0},
+	{2, arcs_60_1},
+	{1, arcs_60_2},
+	{1, arcs_60_3},
+	{1, arcs_60_4},
 };
-static arc arcs_59_0[3] = {
+static arc arcs_61_0[3] = {
 	{13, 1},
-	{136, 2},
+	{139, 2},
 	{75, 3},
 };
-static arc arcs_59_1[2] = {
+static arc arcs_61_1[2] = {
 	{14, 4},
 	{15, 5},
 };
-static arc arcs_59_2[1] = {
-	{149, 6},
+static arc arcs_61_2[1] = {
+	{152, 6},
 };
-static arc arcs_59_3[1] = {
+static arc arcs_61_3[1] = {
 	{19, 5},
 };
-static arc arcs_59_4[1] = {
+static arc arcs_61_4[1] = {
 	{15, 5},
 };
-static arc arcs_59_5[1] = {
+static arc arcs_61_5[1] = {
 	{0, 5},
 };
-static arc arcs_59_6[1] = {
-	{138, 5},
+static arc arcs_61_6[1] = {
+	{141, 5},
 };
-static state states_59[7] = {
-	{3, arcs_59_0},
-	{2, arcs_59_1},
-	{1, arcs_59_2},
-	{1, arcs_59_3},
-	{1, arcs_59_4},
-	{1, arcs_59_5},
-	{1, arcs_59_6},
+static state states_61[7] = {
+	{3, arcs_61_0},
+	{2, arcs_61_1},
+	{1, arcs_61_2},
+	{1, arcs_61_3},
+	{1, arcs_61_4},
+	{1, arcs_61_5},
+	{1, arcs_61_6},
 };
-static arc arcs_60_0[1] = {
-	{150, 1},
+static arc arcs_62_0[1] = {
+	{153, 1},
 };
-static arc arcs_60_1[2] = {
+static arc arcs_62_1[2] = {
 	{27, 2},
 	{0, 1},
 };
-static arc arcs_60_2[2] = {
-	{150, 1},
+static arc arcs_62_2[2] = {
+	{153, 1},
 	{0, 2},
 };
-static state states_60[3] = {
-	{1, arcs_60_0},
-	{2, arcs_60_1},
-	{2, arcs_60_2},
+static state states_62[3] = {
+	{1, arcs_62_0},
+	{2, arcs_62_1},
+	{2, arcs_62_2},
 };
-static arc arcs_61_0[3] = {
+static arc arcs_63_0[3] = {
 	{75, 1},
 	{26, 2},
 	{21, 3},
 };
-static arc arcs_61_1[1] = {
+static arc arcs_63_1[1] = {
 	{75, 4},
 };
-static arc arcs_61_2[2] = {
+static arc arcs_63_2[2] = {
 	{21, 3},
 	{0, 2},
 };
-static arc arcs_61_3[3] = {
+static arc arcs_63_3[3] = {
 	{26, 5},
-	{151, 6},
+	{154, 6},
 	{0, 3},
 };
-static arc arcs_61_4[1] = {
+static arc arcs_63_4[1] = {
 	{75, 6},
 };
-static arc arcs_61_5[2] = {
-	{151, 6},
+static arc arcs_63_5[2] = {
+	{154, 6},
 	{0, 5},
 };
-static arc arcs_61_6[1] = {
+static arc arcs_63_6[1] = {
 	{0, 6},
 };
-static state states_61[7] = {
-	{3, arcs_61_0},
-	{1, arcs_61_1},
-	{2, arcs_61_2},
-	{3, arcs_61_3},
-	{1, arcs_61_4},
-	{2, arcs_61_5},
-	{1, arcs_61_6},
+static state states_63[7] = {
+	{3, arcs_63_0},
+	{1, arcs_63_1},
+	{2, arcs_63_2},
+	{3, arcs_63_3},
+	{1, arcs_63_4},
+	{2, arcs_63_5},
+	{1, arcs_63_6},
 };
-static arc arcs_62_0[1] = {
+static arc arcs_64_0[1] = {
 	{21, 1},
 };
-static arc arcs_62_1[2] = {
+static arc arcs_64_1[2] = {
 	{26, 2},
 	{0, 1},
 };
-static arc arcs_62_2[1] = {
+static arc arcs_64_2[1] = {
 	{0, 2},
 };
-static state states_62[3] = {
-	{1, arcs_62_0},
-	{2, arcs_62_1},
-	{1, arcs_62_2},
+static state states_64[3] = {
+	{1, arcs_64_0},
+	{2, arcs_64_1},
+	{1, arcs_64_2},
 };
-static arc arcs_63_0[1] = {
+static arc arcs_65_0[1] = {
 	{81, 1},
 };
-static arc arcs_63_1[2] = {
+static arc arcs_65_1[2] = {
 	{27, 2},
 	{0, 1},
 };
-static arc arcs_63_2[2] = {
+static arc arcs_65_2[2] = {
 	{81, 1},
 	{0, 2},
 };
-static state states_63[3] = {
-	{1, arcs_63_0},
-	{2, arcs_63_1},
-	{2, arcs_63_2},
+static state states_65[3] = {
+	{1, arcs_65_0},
+	{2, arcs_65_1},
+	{2, arcs_65_2},
 };
-static arc arcs_64_0[1] = {
+static arc arcs_66_0[1] = {
 	{26, 1},
 };
-static arc arcs_64_1[2] = {
+static arc arcs_66_1[2] = {
 	{27, 2},
 	{0, 1},
 };
-static arc arcs_64_2[2] = {
+static arc arcs_66_2[2] = {
 	{26, 1},
 	{0, 2},
 };
-static state states_64[3] = {
-	{1, arcs_64_0},
-	{2, arcs_64_1},
-	{2, arcs_64_2},
+static state states_66[3] = {
+	{1, arcs_66_0},
+	{2, arcs_66_1},
+	{2, arcs_66_2},
 };
-static arc arcs_65_0[1] = {
+static arc arcs_67_0[1] = {
 	{26, 1},
 };
-static arc arcs_65_1[2] = {
+static arc arcs_67_1[2] = {
 	{27, 2},
 	{0, 1},
 };
-static arc arcs_65_2[1] = {
+static arc arcs_67_2[1] = {
 	{26, 3},
 };
-static arc arcs_65_3[2] = {
+static arc arcs_67_3[2] = {
 	{27, 4},
 	{0, 3},
 };
-static arc arcs_65_4[2] = {
+static arc arcs_67_4[2] = {
 	{26, 3},
 	{0, 4},
 };
-static state states_65[5] = {
-	{1, arcs_65_0},
-	{2, arcs_65_1},
-	{1, arcs_65_2},
-	{2, arcs_65_3},
-	{2, arcs_65_4},
+static state states_67[5] = {
+	{1, arcs_67_0},
+	{2, arcs_67_1},
+	{1, arcs_67_2},
+	{2, arcs_67_3},
+	{2, arcs_67_4},
 };
-static arc arcs_66_0[1] = {
+static arc arcs_68_0[1] = {
 	{26, 1},
 };
-static arc arcs_66_1[1] = {
+static arc arcs_68_1[1] = {
 	{21, 2},
 };
-static arc arcs_66_2[1] = {
+static arc arcs_68_2[1] = {
 	{26, 3},
 };
-static arc arcs_66_3[2] = {
+static arc arcs_68_3[2] = {
 	{27, 4},
 	{0, 3},
 };
-static arc arcs_66_4[2] = {
+static arc arcs_68_4[2] = {
 	{26, 1},
 	{0, 4},
 };
-static state states_66[5] = {
-	{1, arcs_66_0},
-	{1, arcs_66_1},
-	{1, arcs_66_2},
-	{2, arcs_66_3},
-	{2, arcs_66_4},
+static state states_68[5] = {
+	{1, arcs_68_0},
+	{1, arcs_68_1},
+	{1, arcs_68_2},
+	{2, arcs_68_3},
+	{2, arcs_68_4},
 };
-static arc arcs_67_0[1] = {
-	{153, 1},
+static arc arcs_69_0[1] = {
+	{156, 1},
 };
-static arc arcs_67_1[1] = {
+static arc arcs_69_1[1] = {
 	{19, 2},
 };
-static arc arcs_67_2[2] = {
+static arc arcs_69_2[2] = {
 	{13, 3},
 	{21, 4},
 };
-static arc arcs_67_3[2] = {
+static arc arcs_69_3[2] = {
 	{9, 5},
 	{15, 6},
 };
-static arc arcs_67_4[1] = {
+static arc arcs_69_4[1] = {
 	{22, 7},
 };
-static arc arcs_67_5[1] = {
+static arc arcs_69_5[1] = {
 	{15, 6},
 };
-static arc arcs_67_6[1] = {
+static arc arcs_69_6[1] = {
 	{21, 4},
 };
-static arc arcs_67_7[1] = {
+static arc arcs_69_7[1] = {
 	{0, 7},
 };
-static state states_67[8] = {
-	{1, arcs_67_0},
-	{1, arcs_67_1},
-	{2, arcs_67_2},
-	{2, arcs_67_3},
-	{1, arcs_67_4},
-	{1, arcs_67_5},
-	{1, arcs_67_6},
-	{1, arcs_67_7},
+static state states_69[8] = {
+	{1, arcs_69_0},
+	{1, arcs_69_1},
+	{2, arcs_69_2},
+	{2, arcs_69_3},
+	{1, arcs_69_4},
+	{1, arcs_69_5},
+	{1, arcs_69_6},
+	{1, arcs_69_7},
 };
-static arc arcs_68_0[3] = {
-	{154, 1},
+static arc arcs_70_0[3] = {
+	{157, 1},
 	{28, 2},
 	{29, 3},
 };
-static arc arcs_68_1[2] = {
+static arc arcs_70_1[2] = {
 	{27, 4},
 	{0, 1},
 };
-static arc arcs_68_2[1] = {
+static arc arcs_70_2[1] = {
 	{26, 5},
 };
-static arc arcs_68_3[1] = {
+static arc arcs_70_3[1] = {
 	{26, 6},
 };
-static arc arcs_68_4[4] = {
-	{154, 1},
+static arc arcs_70_4[4] = {
+	{157, 1},
 	{28, 2},
 	{29, 3},
 	{0, 4},
 };
-static arc arcs_68_5[2] = {
+static arc arcs_70_5[2] = {
 	{27, 7},
 	{0, 5},
 };
-static arc arcs_68_6[1] = {
+static arc arcs_70_6[1] = {
 	{0, 6},
 };
-static arc arcs_68_7[1] = {
+static arc arcs_70_7[1] = {
 	{29, 3},
 };
-static state states_68[8] = {
-	{3, arcs_68_0},
-	{2, arcs_68_1},
-	{1, arcs_68_2},
-	{1, arcs_68_3},
-	{4, arcs_68_4},
-	{2, arcs_68_5},
-	{1, arcs_68_6},
-	{1, arcs_68_7},
+static state states_70[8] = {
+	{3, arcs_70_0},
+	{2, arcs_70_1},
+	{1, arcs_70_2},
+	{1, arcs_70_3},
+	{4, arcs_70_4},
+	{2, arcs_70_5},
+	{1, arcs_70_6},
+	{1, arcs_70_7},
 };
-static arc arcs_69_0[1] = {
+static arc arcs_71_0[1] = {
 	{26, 1},
 };
-static arc arcs_69_1[3] = {
-	{147, 2},
+static arc arcs_71_1[3] = {
+	{150, 2},
 	{25, 3},
 	{0, 1},
 };
-static arc arcs_69_2[1] = {
+static arc arcs_71_2[1] = {
 	{0, 2},
 };
-static arc arcs_69_3[1] = {
+static arc arcs_71_3[1] = {
 	{26, 4},
 };
-static arc arcs_69_4[2] = {
+static arc arcs_71_4[2] = {
 	{13, 5},
 	{0, 4},
 };
-static arc arcs_69_5[1] = {
-	{147, 6},
+static arc arcs_71_5[1] = {
+	{150, 6},
 };
-static arc arcs_69_6[1] = {
+static arc arcs_71_6[1] = {
 	{15, 2},
 };
-static state states_69[7] = {
-	{1, arcs_69_0},
-	{3, arcs_69_1},
-	{1, arcs_69_2},
-	{1, arcs_69_3},
-	{2, arcs_69_4},
-	{1, arcs_69_5},
-	{1, arcs_69_6},
+static state states_71[7] = {
+	{1, arcs_71_0},
+	{3, arcs_71_1},
+	{1, arcs_71_2},
+	{1, arcs_71_3},
+	{2, arcs_71_4},
+	{1, arcs_71_5},
+	{1, arcs_71_6},
 };
-static arc arcs_70_0[2] = {
-	{146, 1},
-	{156, 1},
+static arc arcs_72_0[2] = {
+	{149, 1},
+	{159, 1},
 };
-static arc arcs_70_1[1] = {
+static arc arcs_72_1[1] = {
 	{0, 1},
 };
-static state states_70[2] = {
-	{2, arcs_70_0},
-	{1, arcs_70_1},
+static state states_72[2] = {
+	{2, arcs_72_0},
+	{1, arcs_72_1},
 };
-static arc arcs_71_0[1] = {
-	{93, 1},
+static arc arcs_73_0[1] = {
+	{94, 1},
 };
-static arc arcs_71_1[1] = {
+static arc arcs_73_1[1] = {
 	{59, 2},
 };
-static arc arcs_71_2[1] = {
+static arc arcs_73_2[1] = {
 	{82, 3},
 };
-static arc arcs_71_3[1] = {
-	{152, 4},
+static arc arcs_73_3[1] = {
+	{155, 4},
 };
-static arc arcs_71_4[2] = {
-	{155, 5},
+static arc arcs_73_4[2] = {
+	{158, 5},
 	{0, 4},
 };
-static arc arcs_71_5[1] = {
+static arc arcs_73_5[1] = {
 	{0, 5},
 };
-static state states_71[6] = {
-	{1, arcs_71_0},
-	{1, arcs_71_1},
-	{1, arcs_71_2},
-	{1, arcs_71_3},
-	{2, arcs_71_4},
-	{1, arcs_71_5},
+static state states_73[6] = {
+	{1, arcs_73_0},
+	{1, arcs_73_1},
+	{1, arcs_73_2},
+	{1, arcs_73_3},
+	{2, arcs_73_4},
+	{1, arcs_73_5},
 };
-static arc arcs_72_0[1] = {
-	{89, 1},
+static arc arcs_74_0[1] = {
+	{90, 1},
 };
-static arc arcs_72_1[1] = {
+static arc arcs_74_1[1] = {
 	{26, 2},
 };
-static arc arcs_72_2[2] = {
-	{155, 3},
+static arc arcs_74_2[2] = {
+	{158, 3},
 	{0, 2},
 };
-static arc arcs_72_3[1] = {
+static arc arcs_74_3[1] = {
 	{0, 3},
 };
-static state states_72[4] = {
-	{1, arcs_72_0},
-	{1, arcs_72_1},
-	{2, arcs_72_2},
-	{1, arcs_72_3},
+static state states_74[4] = {
+	{1, arcs_74_0},
+	{1, arcs_74_1},
+	{2, arcs_74_2},
+	{1, arcs_74_3},
 };
-static arc arcs_73_0[2] = {
-	{147, 1},
-	{158, 1},
+static arc arcs_75_0[2] = {
+	{150, 1},
+	{161, 1},
 };
-static arc arcs_73_1[1] = {
+static arc arcs_75_1[1] = {
 	{0, 1},
 };
-static state states_73[2] = {
-	{2, arcs_73_0},
-	{1, arcs_73_1},
+static state states_75[2] = {
+	{2, arcs_75_0},
+	{1, arcs_75_1},
 };
-static arc arcs_74_0[1] = {
-	{93, 1},
+static arc arcs_76_0[1] = {
+	{94, 1},
 };
-static arc arcs_74_1[1] = {
+static arc arcs_76_1[1] = {
 	{59, 2},
 };
-static arc arcs_74_2[1] = {
+static arc arcs_76_2[1] = {
 	{82, 3},
 };
-static arc arcs_74_3[1] = {
+static arc arcs_76_3[1] = {
 	{26, 4},
 };
-static arc arcs_74_4[2] = {
-	{157, 5},
+static arc arcs_76_4[2] = {
+	{160, 5},
 	{0, 4},
 };
-static arc arcs_74_5[1] = {
+static arc arcs_76_5[1] = {
 	{0, 5},
 };
-static state states_74[6] = {
-	{1, arcs_74_0},
-	{1, arcs_74_1},
-	{1, arcs_74_2},
-	{1, arcs_74_3},
-	{2, arcs_74_4},
-	{1, arcs_74_5},
+static state states_76[6] = {
+	{1, arcs_76_0},
+	{1, arcs_76_1},
+	{1, arcs_76_2},
+	{1, arcs_76_3},
+	{2, arcs_76_4},
+	{1, arcs_76_5},
 };
-static arc arcs_75_0[1] = {
-	{89, 1},
+static arc arcs_77_0[1] = {
+	{90, 1},
 };
-static arc arcs_75_1[1] = {
+static arc arcs_77_1[1] = {
 	{26, 2},
 };
-static arc arcs_75_2[2] = {
-	{157, 3},
+static arc arcs_77_2[2] = {
+	{160, 3},
 	{0, 2},
 };
-static arc arcs_75_3[1] = {
+static arc arcs_77_3[1] = {
 	{0, 3},
 };
-static state states_75[4] = {
-	{1, arcs_75_0},
-	{1, arcs_75_1},
-	{2, arcs_75_2},
-	{1, arcs_75_3},
+static state states_77[4] = {
+	{1, arcs_77_0},
+	{1, arcs_77_1},
+	{2, arcs_77_2},
+	{1, arcs_77_3},
 };
-static arc arcs_76_0[1] = {
+static arc arcs_78_0[1] = {
 	{26, 1},
 };
-static arc arcs_76_1[2] = {
+static arc arcs_78_1[2] = {
 	{27, 0},
 	{0, 1},
 };
-static state states_76[2] = {
-	{1, arcs_76_0},
-	{2, arcs_76_1},
+static state states_78[2] = {
+	{1, arcs_78_0},
+	{2, arcs_78_1},
 };
-static arc arcs_77_0[1] = {
+static arc arcs_79_0[1] = {
 	{19, 1},
 };
-static arc arcs_77_1[1] = {
+static arc arcs_79_1[1] = {
 	{0, 1},
 };
-static state states_77[2] = {
-	{1, arcs_77_0},
-	{1, arcs_77_1},
+static state states_79[2] = {
+	{1, arcs_79_0},
+	{1, arcs_79_1},
 };
-static arc arcs_78_0[1] = {
-	{160, 1},
+static arc arcs_80_0[1] = {
+	{163, 1},
 };
-static arc arcs_78_1[2] = {
+static arc arcs_80_1[2] = {
 	{9, 2},
 	{0, 1},
 };
-static arc arcs_78_2[1] = {
+static arc arcs_80_2[1] = {
 	{0, 2},
 };
-static state states_78[3] = {
-	{1, arcs_78_0},
-	{2, arcs_78_1},
-	{1, arcs_78_2},
+static state states_80[3] = {
+	{1, arcs_80_0},
+	{2, arcs_80_1},
+	{1, arcs_80_2},
 };
-static dfa dfas[79] = {
+static dfa dfas[81] = {
 	{256, "single_input", 0, 3, states_0,
-	 "\004\050\014\000\000\000\000\025\074\205\011\162\000\002\000\140\010\111\023\002\001"},
+	 "\004\050\014\000\000\000\000\025\074\205\011\344\004\020\000\000\103\110\232\020\010"},
 	{257, "file_input", 0, 2, states_1,
-	 "\204\050\014\000\000\000\000\025\074\205\011\162\000\002\000\140\010\111\023\002\001"},
+	 "\204\050\014\000\000\000\000\025\074\205\011\344\004\020\000\000\103\110\232\020\010"},
 	{258, "eval_input", 0, 3, states_2,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\002\000\140\010\111\023\000\000"},
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\020\000\000\103\110\232\000\000"},
 	{259, "decorator", 0, 7, states_3,
 	 "\000\010\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000"},
 	{260, "decorators", 0, 2, states_4,
@@ -1712,13 +1764,13 @@
 	{265, "fplist", 0, 3, states_9,
 	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000"},
 	{266, "stmt", 0, 2, states_10,
-	 "\000\050\014\000\000\000\000\025\074\205\011\162\000\002\000\140\010\111\023\002\001"},
+	 "\000\050\014\000\000\000\000\025\074\205\011\344\004\020\000\000\103\110\232\020\010"},
 	{267, "simple_stmt", 0, 4, states_11,
-	 "\000\040\010\000\000\000\000\025\074\205\011\000\000\002\000\140\010\111\023\000\001"},
+	 "\000\040\010\000\000\000\000\025\074\205\011\000\000\020\000\000\103\110\232\000\010"},
 	{268, "small_stmt", 0, 2, states_12,
-	 "\000\040\010\000\000\000\000\025\074\205\011\000\000\002\000\140\010\111\023\000\001"},
+	 "\000\040\010\000\000\000\000\025\074\205\011\000\000\020\000\000\103\110\232\000\010"},
 	{269, "expr_stmt", 0, 6, states_13,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\002\000\140\010\111\023\000\000"},
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\020\000\000\103\110\232\000\000"},
 	{270, "augassign", 0, 2, states_14,
 	 "\000\000\000\000\000\360\377\000\000\000\000\000\000\000\000\000\000\000\000\000\000"},
 	{271, "print_stmt", 0, 9, states_15,
@@ -1728,7 +1780,7 @@
 	{273, "pass_stmt", 0, 2, states_17,
 	 "\000\000\000\000\000\000\000\020\000\000\000\000\000\000\000\000\000\000\000\000\000"},
 	{274, "flow_stmt", 0, 2, states_18,
-	 "\000\000\000\000\000\000\000\000\074\000\000\000\000\000\000\000\000\000\000\000\001"},
+	 "\000\000\000\000\000\000\000\000\074\000\000\000\000\000\000\000\000\000\000\000\010"},
 	{275, "break_stmt", 0, 2, states_19,
 	 "\000\000\000\000\000\000\000\000\004\000\000\000\000\000\000\000\000\000\000\000\000"},
 	{276, "continue_stmt", 0, 2, states_20,
@@ -1736,7 +1788,7 @@
 	{277, "return_stmt", 0, 3, states_21,
 	 "\000\000\000\000\000\000\000\000\020\000\000\000\000\000\000\000\000\000\000\000\000"},
 	{278, "yield_stmt", 0, 2, states_22,
-	 "\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\001"},
+	 "\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\010"},
 	{279, "raise_stmt", 0, 7, states_23,
 	 "\000\000\000\000\000\000\000\000\040\000\000\000\000\000\000\000\000\000\000\000\000"},
 	{280, "import_stmt", 0, 2, states_24,
@@ -1762,95 +1814,99 @@
 	{290, "assert_stmt", 0, 5, states_34,
 	 "\000\000\000\000\000\000\000\000\000\000\010\000\000\000\000\000\000\000\000\000\000"},
 	{291, "compound_stmt", 0, 2, states_35,
-	 "\000\010\004\000\000\000\000\000\000\000\000\162\000\000\000\000\000\000\000\002\000"},
+	 "\000\010\004\000\000\000\000\000\000\000\000\344\004\000\000\000\000\000\000\020\000"},
 	{292, "if_stmt", 0, 8, states_36,
-	 "\000\000\000\000\000\000\000\000\000\000\000\002\000\000\000\000\000\000\000\000\000"},
+	 "\000\000\000\000\000\000\000\000\000\000\000\004\000\000\000\000\000\000\000\000\000"},
 	{293, "while_stmt", 0, 8, states_37,
-	 "\000\000\000\000\000\000\000\000\000\000\000\020\000\000\000\000\000\000\000\000\000"},
+	 "\000\000\000\000\000\000\000\000\000\000\000\040\000\000\000\000\000\000\000\000\000"},
 	{294, "for_stmt", 0, 10, states_38,
-	 "\000\000\000\000\000\000\000\000\000\000\000\040\000\000\000\000\000\000\000\000\000"},
+	 "\000\000\000\000\000\000\000\000\000\000\000\100\000\000\000\000\000\000\000\000\000"},
 	{295, "try_stmt", 0, 13, states_39,
+	 "\000\000\000\000\000\000\000\000\000\000\000\200\000\000\000\000\000\000\000\000\000"},
+	{296, "with_stmt", 0, 6, states_40,
+	 "\000\000\000\000\000\000\000\000\000\000\000\000\004\000\000\000\000\000\000\000\000"},
+	{297, "with_var", 0, 5, states_41,
+	 "\000\000\010\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000"},
+	{298, "except_clause", 0, 5, states_42,
+	 "\000\000\000\000\000\000\000\000\000\000\000\000\020\000\000\000\000\000\000\000\000"},
+	{299, "suite", 0, 5, states_43,
+	 "\004\040\010\000\000\000\000\025\074\205\011\000\000\020\000\000\103\110\232\000\010"},
+	{300, "test", 0, 4, states_44,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\020\000\000\103\110\232\000\000"},
+	{301, "and_test", 0, 2, states_45,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\020\000\000\103\110\032\000\000"},
+	{302, "not_test", 0, 3, states_46,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\020\000\000\103\110\032\000\000"},
+	{303, "comparison", 0, 2, states_47,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\103\110\032\000\000"},
+	{304, "comp_op", 0, 4, states_48,
+	 "\000\000\000\000\000\000\000\000\000\000\004\000\000\220\177\000\000\000\000\000\000"},
+	{305, "expr", 0, 2, states_49,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\103\110\032\000\000"},
+	{306, "xor_expr", 0, 2, states_50,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\103\110\032\000\000"},
+	{307, "and_expr", 0, 2, states_51,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\103\110\032\000\000"},
+	{308, "shift_expr", 0, 2, states_52,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\103\110\032\000\000"},
+	{309, "arith_expr", 0, 2, states_53,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\103\110\032\000\000"},
+	{310, "term", 0, 2, states_54,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\103\110\032\000\000"},
+	{311, "factor", 0, 3, states_55,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\103\110\032\000\000"},
+	{312, "power", 0, 4, states_56,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\000\110\032\000\000"},
+	{313, "atom", 0, 11, states_57,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\000\110\032\000\000"},
+	{314, "listmaker", 0, 5, states_58,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\020\000\000\103\110\232\000\000"},
+	{315, "testlist_gexp", 0, 5, states_59,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\020\000\000\103\110\232\000\000"},
+	{316, "lambdef", 0, 5, states_60,
+	 "\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\200\000\000"},
+	{317, "trailer", 0, 7, states_61,
+	 "\000\040\000\000\000\000\000\000\000\010\000\000\000\000\000\000\000\010\000\000\000"},
+	{318, "subscriptlist", 0, 3, states_62,
+	 "\000\040\050\000\000\000\000\000\000\010\000\000\000\020\000\000\103\110\232\000\000"},
+	{319, "subscript", 0, 7, states_63,
+	 "\000\040\050\000\000\000\000\000\000\010\000\000\000\020\000\000\103\110\232\000\000"},
+	{320, "sliceop", 0, 3, states_64,
+	 "\000\000\040\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000"},
+	{321, "exprlist", 0, 3, states_65,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\103\110\032\000\000"},
+	{322, "testlist", 0, 3, states_66,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\020\000\000\103\110\232\000\000"},
+	{323, "testlist_safe", 0, 5, states_67,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\020\000\000\103\110\232\000\000"},
+	{324, "dictmaker", 0, 5, states_68,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\020\000\000\103\110\232\000\000"},
+	{325, "classdef", 0, 8, states_69,
+	 "\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\020\000"},
+	{326, "arglist", 0, 8, states_70,
+	 "\000\040\010\060\000\000\000\000\000\000\000\000\000\020\000\000\103\110\232\000\000"},
+	{327, "argument", 0, 7, states_71,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\020\000\000\103\110\232\000\000"},
+	{328, "list_iter", 0, 2, states_72,
+	 "\000\000\000\000\000\000\000\000\000\000\000\104\000\000\000\000\000\000\000\000\000"},
+	{329, "list_for", 0, 6, states_73,
 	 "\000\000\000\000\000\000\000\000\000\000\000\100\000\000\000\000\000\000\000\000\000"},
-	{296, "except_clause", 0, 5, states_40,
-	 "\000\000\000\000\000\000\000\000\000\000\000\000\002\000\000\000\000\000\000\000\000"},
-	{297, "suite", 0, 5, states_41,
-	 "\004\040\010\000\000\000\000\025\074\205\011\000\000\002\000\140\010\111\023\000\001"},
-	{298, "test", 0, 4, states_42,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\002\000\140\010\111\023\000\000"},
-	{299, "and_test", 0, 2, states_43,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\002\000\140\010\111\003\000\000"},
-	{300, "not_test", 0, 3, states_44,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\002\000\140\010\111\003\000\000"},
-	{301, "comparison", 0, 2, states_45,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\140\010\111\003\000\000"},
-	{302, "comp_op", 0, 4, states_46,
-	 "\000\000\000\000\000\000\000\000\000\000\004\000\000\362\017\000\000\000\000\000\000"},
-	{303, "expr", 0, 2, states_47,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\140\010\111\003\000\000"},
-	{304, "xor_expr", 0, 2, states_48,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\140\010\111\003\000\000"},
-	{305, "and_expr", 0, 2, states_49,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\140\010\111\003\000\000"},
-	{306, "shift_expr", 0, 2, states_50,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\140\010\111\003\000\000"},
-	{307, "arith_expr", 0, 2, states_51,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\140\010\111\003\000\000"},
-	{308, "term", 0, 2, states_52,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\140\010\111\003\000\000"},
-	{309, "factor", 0, 3, states_53,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\140\010\111\003\000\000"},
-	{310, "power", 0, 4, states_54,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\000\111\003\000\000"},
-	{311, "atom", 0, 11, states_55,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\000\000\111\003\000\000"},
-	{312, "listmaker", 0, 5, states_56,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\002\000\140\010\111\023\000\000"},
-	{313, "testlist_gexp", 0, 5, states_57,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\002\000\140\010\111\023\000\000"},
-	{314, "lambdef", 0, 5, states_58,
-	 "\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\020\000\000"},
-	{315, "trailer", 0, 7, states_59,
-	 "\000\040\000\000\000\000\000\000\000\010\000\000\000\000\000\000\000\001\000\000\000"},
-	{316, "subscriptlist", 0, 3, states_60,
-	 "\000\040\050\000\000\000\000\000\000\010\000\000\000\002\000\140\010\111\023\000\000"},
-	{317, "subscript", 0, 7, states_61,
-	 "\000\040\050\000\000\000\000\000\000\010\000\000\000\002\000\140\010\111\023\000\000"},
-	{318, "sliceop", 0, 3, states_62,
-	 "\000\000\040\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000"},
-	{319, "exprlist", 0, 3, states_63,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\000\000\140\010\111\003\000\000"},
-	{320, "testlist", 0, 3, states_64,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\002\000\140\010\111\023\000\000"},
-	{321, "testlist_safe", 0, 5, states_65,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\002\000\140\010\111\023\000\000"},
-	{322, "dictmaker", 0, 5, states_66,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\002\000\140\010\111\023\000\000"},
-	{323, "classdef", 0, 8, states_67,
-	 "\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\002\000"},
-	{324, "arglist", 0, 8, states_68,
-	 "\000\040\010\060\000\000\000\000\000\000\000\000\000\002\000\140\010\111\023\000\000"},
-	{325, "argument", 0, 7, states_69,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\002\000\140\010\111\023\000\000"},
-	{326, "list_iter", 0, 2, states_70,
-	 "\000\000\000\000\000\000\000\000\000\000\000\042\000\000\000\000\000\000\000\000\000"},
-	{327, "list_for", 0, 6, states_71,
-	 "\000\000\000\000\000\000\000\000\000\000\000\040\000\000\000\000\000\000\000\000\000"},
-	{328, "list_if", 0, 4, states_72,
-	 "\000\000\000\000\000\000\000\000\000\000\000\002\000\000\000\000\000\000\000\000\000"},
-	{329, "gen_iter", 0, 2, states_73,
-	 "\000\000\000\000\000\000\000\000\000\000\000\042\000\000\000\000\000\000\000\000\000"},
-	{330, "gen_for", 0, 6, states_74,
-	 "\000\000\000\000\000\000\000\000\000\000\000\040\000\000\000\000\000\000\000\000\000"},
-	{331, "gen_if", 0, 4, states_75,
-	 "\000\000\000\000\000\000\000\000\000\000\000\002\000\000\000\000\000\000\000\000\000"},
-	{332, "testlist1", 0, 2, states_76,
-	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\002\000\140\010\111\023\000\000"},
-	{333, "encoding_decl", 0, 2, states_77,
+	{330, "list_if", 0, 4, states_74,
+	 "\000\000\000\000\000\000\000\000\000\000\000\004\000\000\000\000\000\000\000\000\000"},
+	{331, "gen_iter", 0, 2, states_75,
+	 "\000\000\000\000\000\000\000\000\000\000\000\104\000\000\000\000\000\000\000\000\000"},
+	{332, "gen_for", 0, 6, states_76,
+	 "\000\000\000\000\000\000\000\000\000\000\000\100\000\000\000\000\000\000\000\000\000"},
+	{333, "gen_if", 0, 4, states_77,
+	 "\000\000\000\000\000\000\000\000\000\000\000\004\000\000\000\000\000\000\000\000\000"},
+	{334, "testlist1", 0, 2, states_78,
+	 "\000\040\010\000\000\000\000\000\000\000\000\000\000\020\000\000\103\110\232\000\000"},
+	{335, "encoding_decl", 0, 2, states_79,
 	 "\000\000\010\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000"},
-	{334, "yield_expr", 0, 3, states_78,
-	 "\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\001"},
+	{336, "yield_expr", 0, 3, states_80,
+	 "\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\010"},
 };
-static label labels[161] = {
+static label labels[164] = {
 	{0, "EMPTY"},
 	{256, 0},
 	{4, 0},
@@ -1860,12 +1916,12 @@
 	{266, 0},
 	{0, 0},
 	{258, 0},
-	{320, 0},
+	{322, 0},
 	{259, 0},
 	{50, 0},
 	{287, 0},
 	{7, 0},
-	{324, 0},
+	{326, 0},
 	{8, 0},
 	{260, 0},
 	{261, 0},
@@ -1873,11 +1929,11 @@
 	{1, 0},
 	{262, 0},
 	{11, 0},
-	{297, 0},
+	{299, 0},
 	{263, 0},
 	{264, 0},
 	{22, 0},
-	{298, 0},
+	{300, 0},
 	{12, 0},
 	{16, 0},
 	{36, 0},
@@ -1894,7 +1950,7 @@
 	{289, 0},
 	{290, 0},
 	{270, 0},
-	{334, 0},
+	{336, 0},
 	{37, 0},
 	{38, 0},
 	{39, 0},
@@ -1910,7 +1966,7 @@
 	{1, "print"},
 	{35, 0},
 	{1, "del"},
-	{319, 0},
+	{321, 0},
 	{1, "pass"},
 	{275, 0},
 	{276, 0},
@@ -1932,33 +1988,36 @@
 	{284, 0},
 	{1, "global"},
 	{1, "exec"},
-	{303, 0},
+	{305, 0},
 	{1, "in"},
 	{1, "assert"},
 	{292, 0},
 	{293, 0},
 	{294, 0},
 	{295, 0},
-	{323, 0},
+	{296, 0},
+	{325, 0},
 	{1, "if"},
 	{1, "elif"},
 	{1, "else"},
 	{1, "while"},
 	{1, "for"},
 	{1, "try"},
-	{296, 0},
+	{298, 0},
 	{1, "finally"},
+	{1, "with"},
+	{297, 0},
 	{1, "except"},
 	{5, 0},
 	{6, 0},
-	{299, 0},
+	{301, 0},
 	{1, "or"},
-	{314, 0},
-	{300, 0},
+	{316, 0},
+	{302, 0},
 	{1, "and"},
 	{1, "not"},
-	{301, 0},
-	{302, 0},
+	{303, 0},
+	{304, 0},
 	{20, 0},
 	{21, 0},
 	{28, 0},
@@ -1967,55 +2026,55 @@
 	{29, 0},
 	{29, 0},
 	{1, "is"},
-	{304, 0},
+	{306, 0},
 	{18, 0},
-	{305, 0},
+	{307, 0},
 	{33, 0},
-	{306, 0},
+	{308, 0},
 	{19, 0},
-	{307, 0},
+	{309, 0},
 	{34, 0},
-	{308, 0},
+	{310, 0},
 	{14, 0},
 	{15, 0},
-	{309, 0},
+	{311, 0},
 	{17, 0},
 	{24, 0},
 	{48, 0},
 	{32, 0},
-	{310, 0},
-	{311, 0},
+	{312, 0},
+	{313, 0},
+	{317, 0},
 	{315, 0},
-	{313, 0},
 	{9, 0},
-	{312, 0},
+	{314, 0},
 	{10, 0},
 	{26, 0},
-	{322, 0},
+	{324, 0},
 	{27, 0},
 	{25, 0},
-	{332, 0},
+	{334, 0},
 	{2, 0},
 	{3, 0},
-	{327, 0},
-	{330, 0},
+	{329, 0},
+	{332, 0},
 	{1, "lambda"},
-	{316, 0},
-	{317, 0},
 	{318, 0},
-	{321, 0},
+	{319, 0},
+	{320, 0},
+	{323, 0},
 	{1, "class"},
-	{325, 0},
-	{326, 0},
+	{327, 0},
 	{328, 0},
-	{329, 0},
+	{330, 0},
 	{331, 0},
 	{333, 0},
+	{335, 0},
 	{1, "yield"},
 };
 grammar _PyParser_Grammar = {
-	79,
+	81,
 	dfas,
-	{161, labels},
+	{164, labels},
 	256
 };
Index: Python/ast.c
===================================================================
--- Python/ast.c	(revision 42536)
+++ Python/ast.c	(working copy)
@@ -2660,7 +2660,91 @@
     return TryFinally(body, finally, LINENO(n), c->c_arena);
 }
 
+static expr_ty
+with_var_name(struct compiling *c, const node *n, int child_num)
+{
+    const node *child = CHILD(n, child_num);
+    expr_ty result;
+
+    REQ(child, dotted_name);
+    if (strcmp(STR(CHILD(child, 0)), "None") == 0) {
+        ast_error(child, "assignment to None");
+        return NULL;
+    }
+    result = ast_for_dotted_name(c, child);
+    return set_context(result, Store, n) != -1 ? result : NULL;
+}
+
+static expr_ty
+ast_for_with_var(struct compiling *c, const node *n)
+{
+    int i, first_child = 1, len = 1;  /* The standard case is "as NAME" */
+    asdl_seq *variables;
+    char *child_str;
+
+    REQ(n, with_var);
+    if (strcmp(STR(CHILD(n, 0)), "as") != 0) {
+        ast_error(n, "expected \"with [context_expr] as [var]\"");
+        return NULL;
+    }
+    child_str = STR(CHILD(n, 1));
+    if (child_str && (strcmp(child_str, "(") == 0)) {
+        /* (NCH(n) - 2) / 2: If a tuple of variables, subtract "as", "(", and
+         * ")" from the child count, add one back to count the first element
+         * of the tuple, and divide by two to eliminate "," between remaining
+         * elements. */
+        len = (NCH(n) - 2) / 2;
+        assert(len > 0);  /* Grammar should enforce this */
+        first_child = 2;
+    }
+    else {
+        return with_var_name(c, n, first_child);
+    }
+    variables = asdl_seq_new(len, c->c_arena);
+
+    if (!variables)
+        return NULL;
+
+    for (i = 0; i != len; ++i) {
+        expr_ty variable = with_var_name(c, n, (2 * i) + first_child);
+        if (!variable) {
+            return NULL;
+        }
+        asdl_seq_SET(variables, i, variable);
+    }
+    return Tuple(variables, Store, LINENO(n), c->c_arena);
+}
+
+/* with_stmt: 'with' test [ with_var ] ':' suite */
 static stmt_ty
+ast_for_with_stmt(struct compiling *c, const node *n)
+{
+    expr_ty context_expr, optional_vars = NULL;
+    int suite_index = 3;    /* skip 'with', test, and ':' */
+    asdl_seq *suite_seq;
+
+    assert(TYPE(n) == with_stmt);
+    context_expr = ast_for_expr(c, CHILD(n, 1));
+    if (set_context(context_expr, Load, n) == -1) {
+        return NULL;
+    }
+    if (TYPE(CHILD(n, 2)) == with_var) {
+        optional_vars = ast_for_with_var(c, CHILD(n, 2));
+
+        if (!optional_vars) {
+          return NULL;
+        }
+        suite_index = 4;
+    }
+
+    suite_seq = ast_for_suite(c, CHILD(n, suite_index));
+    if (!suite_seq) {
+        return NULL;
+    }
+    return With(context_expr, optional_vars, suite_seq, LINENO(n), c->c_arena);
+}
+
+static stmt_ty
 ast_for_classdef(struct compiling *c, const node *n)
 {
     /* classdef: 'class' NAME ['(' testlist ')'] ':' suite */
@@ -2760,6 +2844,8 @@
                 return ast_for_for_stmt(c, ch);
             case try_stmt:
                 return ast_for_try_stmt(c, ch);
+            case with_stmt:
+                return ast_for_with_stmt(c, ch);
             case funcdef:
                 return ast_for_funcdef(c, ch);
             case classdef:
Index: Python/symtable.c
===================================================================
--- Python/symtable.c	(revision 42536)
+++ Python/symtable.c	(working copy)
@@ -1051,6 +1051,13 @@
         case Continue_kind:
 		/* nothing to do here */
 		break;
+        case With_kind:
+                VISIT(st, expr, s->v.With.context_expr);
+                if (s->v.With.optional_vars) {
+                        VISIT(st, expr, s->v.With.optional_vars);
+                }
+                VISIT_SEQ(st, stmt, s->v.With.body);
+                break;
 	}
 	return 1;
 }
Index: Python/compile.c
===================================================================
--- Python/compile.c	(revision 42536)
+++ Python/compile.c	(working copy)
@@ -191,6 +191,8 @@
 static int inplace_binop(struct compiler *, operator_ty);
 static int expr_constant(expr_ty e);
 
+static int compiler_with(struct compiler *, stmt_ty);
+
 static PyCodeObject *assemble(struct compiler *, int addNone);
 static PyObject *__doc__;
 
@@ -2639,6 +2641,8 @@
 		break;
         case Continue_kind:
 		return compiler_continue(c);
+        case With_kind:
+                return compiler_with(c, s);
 	}
 	return 1;
 }
@@ -3267,7 +3271,158 @@
 	}
 }
 
+/*
+   Implements the with statement from PEP 343.
+
+   The semantics outlined in that PEP are as follows:  
+
+   with EXPR as VAR:
+       BLOCK
+
+   context = (EXPR).__context__()
+   exc = (None, None, None)
+   VAR = context.__enter__()
+   try:
+       try:
+           BLOCK
+       except:
+           exc = sys.exc_info()
+           raise
+   finally:
+       context.__exit__(*exc)
+  
+   Here, it's implemented roughly as:
+  
+   context = (EXPR).__context__()
+   VAR = context.__enter__()
+   try:
+       BLOCK
+       exc = (None, None, None)
+   finally:
+       if an exception was raised:
+         exc = copy of (exception, instance, traceback)
+       context.__exit__(*exc)
+       reraise the exception, if one was raised
+ */
 static int
+compiler_with(struct compiler *c, stmt_ty s)
+{
+    static identifier context_attr, enter_attr, exit_attr;
+    basicblock *block, *finally, *finally_end;
+
+    assert(s->kind == With_kind);
+
+    if (!context_attr) {
+        context_attr = PyString_InternFromString("__context__");
+        if (!context_attr)
+            return 0;
+    }
+    if (!enter_attr) {
+        enter_attr = PyString_InternFromString("__enter__");
+        if (!enter_attr)
+            return 0;
+    }
+    if (!exit_attr) {
+        exit_attr = PyString_InternFromString("__exit__");
+        if (!exit_attr)
+            return 0;
+    }
+
+    block = compiler_new_block(c);
+    finally = compiler_new_block(c);
+    finally_end = compiler_new_block(c);
+    if (!(block || finally || finally_end)) {
+        return 0;
+    }
+
+    /* Evaluate EXPR, evaluate __context__() on the result, and grab a handle
+     * to the result of __context__() */
+    VISIT(c, expr, s->v.With.context_expr);
+    ADDOP_O(c, LOAD_ATTR, context_attr, names);
+    ADDOP_I(c, CALL_FUNCTION, 0);
+
+    ADDOP(c, DUP_TOP);
+    ADDOP_O(c, LOAD_ATTR, enter_attr, names);
+    ADDOP_I(c, CALL_FUNCTION, 0);
+
+    if (s->v.With.optional_vars) {
+        /* bind context.__enter__() to VAR */
+        VISIT(c, expr, s->v.With.optional_vars);
+    }
+    else {
+        ADDOP(c, POP_TOP);
+    }
+    ADDOP_O(c, LOAD_ATTR, exit_attr, names);
+    ADDOP_JREL(c, SETUP_FINALLY, finally);
+
+    compiler_use_next_block(c, block);
+    if (!compiler_push_fblock(c, FINALLY_TRY, block)) {
+        return 0;
+    }
+
+    /* BLOCK code */
+    VISIT_SEQ(c, stmt, s->v.With.body);
+    ADDOP(c, POP_BLOCK);
+    compiler_pop_fblock(c, FINALLY_TRY, block);
+
+    /* BLOCK finished without error.  Put None after __exit__ reference result
+     * to keep END_FINALLY happy after the eventual call to __exit__(). */
+    ADDOP_O(c, LOAD_CONST, Py_None, consts);
+    ADDOP(c, ROT_TWO);
+    ADDOP_O(c, LOAD_CONST, Py_None, consts);
+    ADDOP_O(c, LOAD_CONST, Py_None, consts);
+    ADDOP_O(c, LOAD_CONST, Py_None, consts);
+    ADDOP_I(c, BUILD_TUPLE, 3);
+
+    /* Push None to indicate that no error occurred during the comparison at
+     * the start of the finally block. */
+    ADDOP_O(c, LOAD_CONST, Py_None, consts);
+    compiler_use_next_block(c, finally);
+    if (!compiler_push_fblock(c, FINALLY_END, finally)) {
+        return 0;
+    }
+
+    /* If an exception occurred, we need to preserve the exception information
+       on the stack, for the sake of the END_FINALLY operation, but make a
+       copy of it to pass to __exit__() before that operation occurs.
+      
+       It's ugly.  I know.
+      
+     * if error occurred: */
+    ADDOP(c, DUP_TOP);
+    ADDOP_O(c, LOAD_CONST, Py_None, consts);
+    ADDOP_I(c, COMPARE_OP, PyCmp_IS);
+    ADDOP_JREL(c, JUMP_IF_TRUE, finally_end);
+    ADDOP(c, POP_TOP);
+    /* move __exit__ reference to top of stack */
+    ADDOP(c, ROT_FOUR);
+    ADDOP(c, ROT_FOUR);
+    ADDOP(c, ROT_FOUR);
+    /* copy __exit__ reference and three exception values */
+    ADDOP_I(c, DUP_TOPX, 4);
+    /* move topmost __exit__ underneath exception values and make a tuple */
+    ADDOP(c, ROT_FOUR);
+    ADDOP(c, ROT_THREE);
+    ADDOP(c, ROT_TWO);
+    ADDOP_I(c, BUILD_TUPLE, 3);
+    /* place two stale __exit__references on top (popped in the next block) */
+    ADDOP(c, ROT_TWO);
+    ADDOP(c, DUP_TOP);
+
+    /* Final block starts; should start with two discardable references (i.e.
+       the comparison result from the previous block, and the object used in
+     * the comparison). */
+    compiler_use_next_block(c, finally_end);
+    ADDOP(c, POP_TOP);
+    ADDOP(c, POP_TOP);
+    ADDOP_I(c, CALL_FUNCTION_VAR, 0);
+    ADDOP(c, POP_TOP);  /* discard the result of the function call */
+    ADDOP(c, END_FINALLY);
+    compiler_pop_fblock(c, FINALLY_END, finally);
+    return 1;
+}
+
+static int
 compiler_visit_expr(struct compiler *c, expr_ty e)
 {
 	int i, n;
Index: Python/Python-ast.c
===================================================================
--- Python/Python-ast.c	(revision 42536)
+++ Python/Python-ast.c	(working copy)
@@ -307,6 +307,29 @@
 }
 
 stmt_ty
+With(expr_ty context_expr, expr_ty optional_vars, asdl_seq * body, int lineno,
+     PyArena *arena)
+{
+        stmt_ty p;
+        if (!context_expr) {
+                PyErr_SetString(PyExc_ValueError,
+                                "field context_expr is required for With");
+                return NULL;
+        }
+        p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+        if (!p) {
+                PyErr_NoMemory();
+                return NULL;
+        }
+        p->kind = With_kind;
+        p->v.With.context_expr = context_expr;
+        p->v.With.optional_vars = optional_vars;
+        p->v.With.body = body;
+        p->lineno = lineno;
+        return p;
+}
+
+stmt_ty
 Raise(expr_ty type, expr_ty inst, expr_ty tback, int lineno, PyArena *arena)
 {
         stmt_ty p;
@@ -1333,8 +1356,24 @@
                         marshal_write_stmt(buf, off, (stmt_ty)elt);
                 }
                 break;
+        case With_kind:
+                marshal_write_int(buf, off, 11);
+                marshal_write_expr(buf, off, o->v.With.context_expr);
+                if (o->v.With.optional_vars) {
+                        marshal_write_int(buf, off, 1);
+                        marshal_write_expr(buf, off, o->v.With.optional_vars);
+                }
+                else {
+                        marshal_write_int(buf, off, 0);
+                }
+                marshal_write_int(buf, off, asdl_seq_LEN(o->v.With.body));
+                for (i = 0; i < asdl_seq_LEN(o->v.With.body); i++) {
+                        void *elt = asdl_seq_GET(o->v.With.body, i);
+                        marshal_write_stmt(buf, off, (stmt_ty)elt);
+                }
+                break;
         case Raise_kind:
-                marshal_write_int(buf, off, 11);
+                marshal_write_int(buf, off, 12);
                 if (o->v.Raise.type) {
                         marshal_write_int(buf, off, 1);
                         marshal_write_expr(buf, off, o->v.Raise.type);
@@ -1358,7 +1397,7 @@
                 }
                 break;
         case TryExcept_kind:
-                marshal_write_int(buf, off, 12);
+                marshal_write_int(buf, off, 13);
                 marshal_write_int(buf, off, asdl_seq_LEN(o->v.TryExcept.body));
                 for (i = 0; i < asdl_seq_LEN(o->v.TryExcept.body); i++) {
                         void *elt = asdl_seq_GET(o->v.TryExcept.body, i);
@@ -1379,7 +1418,7 @@
                 }
                 break;
         case TryFinally_kind:
-                marshal_write_int(buf, off, 13);
+                marshal_write_int(buf, off, 14);
                 marshal_write_int(buf, off, asdl_seq_LEN(o->v.TryFinally.body));
                 for (i = 0; i < asdl_seq_LEN(o->v.TryFinally.body); i++) {
                         void *elt = asdl_seq_GET(o->v.TryFinally.body, i);
@@ -1393,7 +1432,7 @@
                 }
                 break;
         case Assert_kind:
-                marshal_write_int(buf, off, 14);
+                marshal_write_int(buf, off, 15);
                 marshal_write_expr(buf, off, o->v.Assert.test);
                 if (o->v.Assert.msg) {
                         marshal_write_int(buf, off, 1);
@@ -1404,7 +1443,7 @@
                 }
                 break;
         case Import_kind:
-                marshal_write_int(buf, off, 15);
+                marshal_write_int(buf, off, 16);
                 marshal_write_int(buf, off, asdl_seq_LEN(o->v.Import.names));
                 for (i = 0; i < asdl_seq_LEN(o->v.Import.names); i++) {
                         void *elt = asdl_seq_GET(o->v.Import.names, i);
@@ -1412,7 +1451,7 @@
                 }
                 break;
         case ImportFrom_kind:
-                marshal_write_int(buf, off, 16);
+                marshal_write_int(buf, off, 17);
                 marshal_write_identifier(buf, off, o->v.ImportFrom.module);
                 marshal_write_int(buf, off,
                                   asdl_seq_LEN(o->v.ImportFrom.names));
@@ -1422,7 +1461,7 @@
                 }
                 break;
         case Exec_kind:
-                marshal_write_int(buf, off, 17);
+                marshal_write_int(buf, off, 18);
                 marshal_write_expr(buf, off, o->v.Exec.body);
                 if (o->v.Exec.globals) {
                         marshal_write_int(buf, off, 1);
@@ -1440,7 +1479,7 @@
                 }
                 break;
         case Global_kind:
-                marshal_write_int(buf, off, 18);
+                marshal_write_int(buf, off, 19);
                 marshal_write_int(buf, off, asdl_seq_LEN(o->v.Global.names));
                 for (i = 0; i < asdl_seq_LEN(o->v.Global.names); i++) {
                         void *elt = asdl_seq_GET(o->v.Global.names, i);
@@ -1448,17 +1487,17 @@
                 }
                 break;
         case Expr_kind:
-                marshal_write_int(buf, off, 19);
+                marshal_write_int(buf, off, 20);
                 marshal_write_expr(buf, off, o->v.Expr.value);
                 break;
         case Pass_kind:
-                marshal_write_int(buf, off, 20);
+                marshal_write_int(buf, off, 21);
                 break;
         case Break_kind:
-                marshal_write_int(buf, off, 21);
+                marshal_write_int(buf, off, 22);
                 break;
         case Continue_kind:
-                marshal_write_int(buf, off, 22);
+                marshal_write_int(buf, off, 23);
                 break;
         }
         return 1;
Index: Include/graminit.h
===================================================================
--- Include/graminit.h	(revision 42536)
+++ Include/graminit.h	(working copy)
@@ -38,42 +38,44 @@
 #define while_stmt 293
 #define for_stmt 294
 #define try_stmt 295
-#define except_clause 296
-#define suite 297
-#define test 298
-#define and_test 299
-#define not_test 300
-#define comparison 301
-#define comp_op 302
-#define expr 303
-#define xor_expr 304
-#define and_expr 305
-#define shift_expr 306
-#define arith_expr 307
-#define term 308
-#define factor 309
-#define power 310
-#define atom 311
-#define listmaker 312
-#define testlist_gexp 313
-#define lambdef 314
-#define trailer 315
-#define subscriptlist 316
-#define subscript 317
-#define sliceop 318
-#define exprlist 319
-#define testlist 320
-#define testlist_safe 321
-#define dictmaker 322
-#define classdef 323
-#define arglist 324
-#define argument 325
-#define list_iter 326
-#define list_for 327
-#define list_if 328
-#define gen_iter 329
-#define gen_for 330
-#define gen_if 331
-#define testlist1 332
-#define encoding_decl 333
-#define yield_expr 334
+#define with_stmt 296
+#define with_var 297
+#define except_clause 298
+#define suite 299
+#define test 300
+#define and_test 301
+#define not_test 302
+#define comparison 303
+#define comp_op 304
+#define expr 305
+#define xor_expr 306
+#define and_expr 307
+#define shift_expr 308
+#define arith_expr 309
+#define term 310
+#define factor 311
+#define power 312
+#define atom 313
+#define listmaker 314
+#define testlist_gexp 315
+#define lambdef 316
+#define trailer 317
+#define subscriptlist 318
+#define subscript 319
+#define sliceop 320
+#define exprlist 321
+#define testlist 322
+#define testlist_safe 323
+#define dictmaker 324
+#define classdef 325
+#define arglist 326
+#define argument 327
+#define list_iter 328
+#define list_for 329
+#define list_if 330
+#define gen_iter 331
+#define gen_for 332
+#define gen_if 333
+#define testlist1 334
+#define encoding_decl 335
+#define yield_expr 336
Index: Include/Python-ast.h
===================================================================
--- Include/Python-ast.h	(revision 42536)
+++ Include/Python-ast.h	(working copy)
@@ -61,11 +61,11 @@
 struct _stmt {
         enum { FunctionDef_kind=1, ClassDef_kind=2, Return_kind=3,
                Delete_kind=4, Assign_kind=5, AugAssign_kind=6, Print_kind=7,
-               For_kind=8, While_kind=9, If_kind=10, Raise_kind=11,
-               TryExcept_kind=12, TryFinally_kind=13, Assert_kind=14,
-               Import_kind=15, ImportFrom_kind=16, Exec_kind=17,
-               Global_kind=18, Expr_kind=19, Pass_kind=20, Break_kind=21,
-               Continue_kind=22 } kind;
+               For_kind=8, While_kind=9, If_kind=10, With_kind=11,
+               Raise_kind=12, TryExcept_kind=13, TryFinally_kind=14,
+               Assert_kind=15, Import_kind=16, ImportFrom_kind=17,
+               Exec_kind=18, Global_kind=19, Expr_kind=20, Pass_kind=21,
+               Break_kind=22, Continue_kind=23 } kind;
         union {
                 struct {
                         identifier name;
@@ -125,6 +125,12 @@
                 } If;
                 
                 struct {
+                        expr_ty context_expr;
+                        expr_ty optional_vars;
+                        asdl_seq *body;
+                } With;
+                
+                struct {
                         expr_ty type;
                         expr_ty inst;
                         expr_ty tback;
@@ -349,6 +355,8 @@
               PyArena *arena);
 stmt_ty If(expr_ty test, asdl_seq * body, asdl_seq * orelse, int lineno,
            PyArena *arena);
+stmt_ty With(expr_ty context_expr, expr_ty optional_vars, asdl_seq * body, int
+             lineno, PyArena *arena);
 stmt_ty Raise(expr_ty type, expr_ty inst, expr_ty tback, int lineno, PyArena
               *arena);
 stmt_ty TryExcept(asdl_seq * body, asdl_seq * handlers, asdl_seq * orelse, int
Index: Grammar/Grammar
===================================================================
--- Grammar/Grammar	(revision 42536)
+++ Grammar/Grammar	(working copy)
@@ -70,7 +70,7 @@
 exec_stmt: 'exec' expr ['in' test [',' test]]
 assert_stmt: 'assert' test [',' test]
 
-compound_stmt: if_stmt | while_stmt | for_stmt | try_stmt | funcdef | classdef
+compound_stmt: if_stmt | while_stmt | for_stmt | try_stmt | with_stmt | funcdef | classdef
 if_stmt: 'if' test ':' suite ('elif' test ':' suite)* ['else' ':' suite]
 while_stmt: 'while' test ':' suite ['else' ':' suite]
 for_stmt: 'for' exprlist 'in' testlist ':' suite ['else' ':' suite]
@@ -79,6 +79,8 @@
 	    ['else' ':' suite]
 	    ['finally' ':' suite] |
 	   'finally' ':' suite))
+with_stmt: 'with' test [ with_var ] ':' suite
+with_var: NAME (dotted_name | '(' dotted_name (',' dotted_name)* ')')
 # NB compile.c makes sure that the default except clause is last
 except_clause: 'except' [test [',' test]]
 suite: simple_stmt | NEWLINE INDENT stmt+ DEDENT
Index: Misc/ACKS
===================================================================
--- Misc/ACKS	(revision 42536)
+++ Misc/ACKS	(working copy)
@@ -62,6 +62,7 @@
 Philippe Biondi
 Stuart Bishop
 Roy Bixler
+Mike Bland
 Martin Bless
 Pablo Bleyer
 Erik van Blokland
Index: Misc/NEWS
===================================================================
--- Misc/NEWS	(revision 42536)
+++ Misc/NEWS	(working copy)
@@ -12,6 +12,8 @@
 Core and builtins
 -----------------
 
+- PEP 343: with statement implemented.
+
 - Fix the encodings package codec search function to only search
   inside its own package. Fixes problem reported in patch #1433198.
 
Index: Parser/Python.asdl
===================================================================
--- Parser/Python.asdl	(revision 42536)
+++ Parser/Python.asdl	(working copy)
@@ -25,6 +25,7 @@
 	      | For(expr target, expr iter, stmt* body, stmt* orelse)
 	      | While(expr test, stmt* body, stmt* orelse)
 	      | If(expr test, stmt* body, stmt* orelse)
+          | With(expr context_expr, expr? optional_vars, stmt* body)
 
 	      -- 'type' is a bad name
 	      | Raise(expr? type, expr? inst, expr? tback)
Index: Tools/compiler/ast.txt
===================================================================
--- Tools/compiler/ast.txt	(revision 42536)
+++ Tools/compiler/ast.txt	(working copy)
@@ -20,6 +20,7 @@
 Continue: 
 For: assign, list, body, else_&
 While: test, body, else_&
+With: expr, vars&, body
 If: tests!, else_&
 Exec: expr, locals&, globals&
 From: modname*, names*
@@ -42,7 +43,7 @@
 ListComp: expr, quals!
 ListCompFor: assign, list, ifs!
 ListCompIf: test
-GenExpr: code 
+GenExpr: code
 GenExprInner: expr, quals!
 GenExprFor: assign, iter, ifs!
 GenExprIf: test
Index: Doc/lib/asttable.tex
===================================================================
--- Doc/lib/asttable.tex	(revision 42536)
+++ Doc/lib/asttable.tex	(working copy)
@@ -272,6 +272,11 @@
 \lineiii{}{\member{else_}}{}
 \hline 
 
+\lineiii{With}{\member{expr}}{}
+\lineiii{}{\member{vars&}}{}
+\lineiii{}{\member{body}}{}
+\hline 
+
 \lineiii{Yield}{\member{value}}{}
 \hline 
 
Index: Doc/ref/ref7.tex
===================================================================
--- Doc/ref/ref7.tex	(revision 42536)
+++ Doc/ref/ref7.tex	(working copy)
@@ -308,6 +308,12 @@
 statement to generate exceptions may be found in section~\ref{raise}.
 
 
+\section{The \keyword{with} statement\label{with}}
+\stindex{with}
+
+The \keyword{with} statement specifies 
+
+
 \section{Function definitions\label{function}}
 \indexii{function}{definition}
 \stindex{def}
Index: Lib/symbol.py
===================================================================
--- Lib/symbol.py	(revision 42536)
+++ Lib/symbol.py	(working copy)
@@ -50,45 +50,47 @@
 while_stmt = 293
 for_stmt = 294
 try_stmt = 295
-except_clause = 296
-suite = 297
-test = 298
-and_test = 299
-not_test = 300
-comparison = 301
-comp_op = 302
-expr = 303
-xor_expr = 304
-and_expr = 305
-shift_expr = 306
-arith_expr = 307
-term = 308
-factor = 309
-power = 310
-atom = 311
-listmaker = 312
-testlist_gexp = 313
-lambdef = 314
-trailer = 315
-subscriptlist = 316
-subscript = 317
-sliceop = 318
-exprlist = 319
-testlist = 320
-testlist_safe = 321
-dictmaker = 322
-classdef = 323
-arglist = 324
-argument = 325
-list_iter = 326
-list_for = 327
-list_if = 328
-gen_iter = 329
-gen_for = 330
-gen_if = 331
-testlist1 = 332
-encoding_decl = 333
-yield_expr = 334
+with_stmt = 296
+with_var = 297
+except_clause = 298
+suite = 299
+test = 300
+and_test = 301
+not_test = 302
+comparison = 303
+comp_op = 304
+expr = 305
+xor_expr = 306
+and_expr = 307
+shift_expr = 308
+arith_expr = 309
+term = 310
+factor = 311
+power = 312
+atom = 313
+listmaker = 314
+testlist_gexp = 315
+lambdef = 316
+trailer = 317
+subscriptlist = 318
+subscript = 319
+sliceop = 320
+exprlist = 321
+testlist = 322
+testlist_safe = 323
+dictmaker = 324
+classdef = 325
+arglist = 326
+argument = 327
+list_iter = 328
+list_for = 329
+list_if = 330
+gen_iter = 331
+gen_for = 332
+gen_if = 333
+testlist1 = 334
+encoding_decl = 335
+yield_expr = 336
 #--end constants--
 
 sym_name = {}
Index: Lib/nested.py
===================================================================
--- Lib/nested.py	(revision 0)
+++ Lib/nested.py	(revision 0)
@@ -0,0 +1,41 @@
+import sys
+from collections import deque
+
+
+class nested(object):
+    def __init__(self, *contexts):
+        self.contexts = contexts
+        self.entered = None
+
+    def __context__(self):
+        return self
+
+    def __enter__(self):
+        if self.entered is not None:
+            raise RuntimeError("Context is not reentrant")
+        self.entered = deque()
+        vars = []
+        try:
+            for context in self.contexts:
+                mgr = context.__context__()
+                vars.append(mgr.__enter__())
+                self.entered.appendleft(mgr)
+        except:
+            self.__exit__(*sys.exc_info())
+            raise
+        return vars
+
+    def __exit__(self, *exc_info):
+        # Behave like nested with statements
+        # first in, last out
+        # New exceptions override old ones
+        ex = exc_info
+        for mgr in self.entered:
+            try:
+                mgr.__exit__(*ex)
+            except:
+                ex = sys.exc_info()
+        self.entered = None
+        if ex is not exc_info:
+            raise ex[0], ex[1], ex[2]
+
Index: Lib/contextmanager.py
===================================================================
--- Lib/contextmanager.py	(revision 0)
+++ Lib/contextmanager.py	(revision 0)
@@ -0,0 +1,34 @@
+class GeneratorContextManager(object):
+    def __init__(self, gen):
+        self.gen = gen
+
+    def __context__(self):
+        return self
+
+    def __enter__(self):
+        try:
+            return self.gen.next()
+        except StopIteration:
+            raise RuntimeError("generator didn't yield")
+
+    def __exit__(self, type, value, traceback):
+        if type is None:
+            try:
+                self.gen.next()
+            except StopIteration:
+                return
+            else:
+                raise RuntimeError("generator didn't stop")
+        else:
+            try:
+                self.gen.throw(type, value, traceback)
+            except (type, StopIteration):
+                return
+            else:
+                raise RuntimeError("generator caught exception")
+
+def contextmanager(func):
+    def helper(*args, **kwds):
+        return GeneratorContextManager(func(*args, **kwds))
+    return helper
+
Index: Lib/compiler/ast.py
===================================================================
--- Lib/compiler/ast.py	(revision 42536)
+++ Lib/compiler/ast.py	(working copy)
@@ -553,9 +553,9 @@
             self.varargs = 1
         if flags & CO_VARKEYWORDS:
             self.kwargs = 1
+    
 
 
-
     def getChildren(self):
         children = []
         children.append(self.decorators)
@@ -584,9 +584,9 @@
         self.lineno = lineno
         self.argnames = ['[outmost-iterable]']
         self.varargs = self.kwargs = None
+    
 
 
-
     def getChildren(self):
         return self.code,
 
@@ -763,9 +763,9 @@
             self.varargs = 1
         if flags & CO_VARKEYWORDS:
             self.kwargs = 1
+    
 
 
-
     def getChildren(self):
         children = []
         children.append(self.argnames)
@@ -1297,6 +1297,31 @@
     def __repr__(self):
         return "While(%s, %s, %s)" % (repr(self.test), repr(self.body), repr(self.else_))
 
+class With(Node):
+    def __init__(self, expr, vars, body, lineno=None):
+        self.expr = expr
+        self.vars = vars
+        self.body = body
+        self.lineno = lineno
+
+    def getChildren(self):
+        children = []
+        children.append(self.expr)
+        children.append(self.vars)
+        children.append(self.body)
+        return tuple(children)
+
+    def getChildNodes(self):
+        nodelist = []
+        nodelist.append(self.expr)
+        if self.vars is not None:
+            nodelist.append(self.vars)
+        nodelist.append(self.body)
+        return tuple(nodelist)
+
+    def __repr__(self):
+        return "With(%s, %s, %s)" % (repr(self.expr), repr(self.vars), repr(self.body))
+
 class Yield(Node):
     def __init__(self, value, lineno=None):
         self.value = value
Index: Lib/test/test_with.py
===================================================================
--- Lib/test/test_with.py	(revision 0)
+++ Lib/test/test_with.py	(revision 0)
@@ -0,0 +1,453 @@
+#!/usr/bin/env python
+
+'''
+Tests for the with statement specified in PEP 343.
+'''
+
+__author__ = "Mike Bland"
+__email__ = "mbland at acm dot org"
+__version__ = ""
+
+import unittest
+from contextmanager import GeneratorContextManager
+from nested import nested
+from test.test_support import run_unittest
+
+
+class MockContextManager(GeneratorContextManager):
+    def __init__(self, gen):
+        GeneratorContextManager.__init__(self, gen)
+        self.context_called = False
+        self.enter_called = False
+        self.exit_called = False
+        self.exit_args = None
+
+    def __context__(self):
+        self.context_called = True
+        return GeneratorContextManager.__context__(self)
+
+    def __enter__(self):
+        self.enter_called = True
+        return GeneratorContextManager.__enter__(self)
+
+    def __exit__(self, type, value, traceback):
+        self.exit_called = True
+        self.exit_args = (type, value, traceback)
+        return GeneratorContextManager.__exit__(self, type, value, traceback)
+
+
+def mock_contextmanager(func):
+    def helper(*args, **kwds):
+        return MockContextManager(func(*args, **kwds))
+    return helper
+
+
+class MockResource(object):
+    def __init__(self):
+        self.yielded = False
+        self.stopped = False
+
+
+@mock_contextmanager
+def mock_contextmanager_generator():
+    mock = MockResource()
+    try:
+        mock.yielded = True
+        yield mock
+    finally:
+        mock.stopped = True
+
+
+class MockNested(nested):
+    def __init__(self, *contexts):
+        nested.__init__(self, *contexts)
+        self.context_called = False
+        self.enter_called = False
+        self.exit_called = False
+        self.exit_args = None
+
+    def __context__(self):
+        self.context_called = True
+        return nested.__context__(self)
+
+    def __enter__(self):
+        self.enter_called = True
+        return nested.__enter__(self)
+
+    def __exit__(self, *exc_info):
+        self.exit_called = True
+        self.exit_args = exc_info
+        return nested.__exit__(self, *exc_info)
+
+ 
+class FailureTestCase(unittest.TestCase):
+    def testNameError(self):
+        def fooNotDeclared():
+            with foo: pass
+        self.assertRaises(NameError, fooNotDeclared)
+
+    def testContextAttributeError(self):
+        class LacksContext(object):
+            def __enter__(self):
+                pass
+
+            def __exit__(self, type, value, traceback):
+                pass
+
+        def fooLacksContext():
+            foo = LacksContext()
+            with foo: pass
+        self.assertRaises(AttributeError, fooLacksContext)
+
+    def testEnterAttributeError(self):
+        class LacksEnter(object):
+            def __context__(self):
+                pass
+
+            def __exit__(self, type, value, traceback):
+                pass
+
+        def fooLacksEnter():
+            foo = LacksEnter()
+            with foo: pass
+        self.assertRaises(AttributeError, fooLacksEnter)
+
+    def testExitAttributeError(self):
+        class LacksExit(object):
+            def __context__(self):
+                pass
+
+            def __enter__(self):
+                pass
+
+        def fooLacksExit():
+            foo = LacksExit()
+            with foo: pass
+        self.assertRaises(AttributeError, fooLacksExit)
+
+    def assertRaisesSyntaxError(self, codestr):
+        def shouldRaiseSyntaxError(s):
+            compile(s, '', 'single')
+        self.assertRaises(SyntaxError, shouldRaiseSyntaxError, codestr)
+
+    def testAssignmentToNoneError(self):
+        self.assertRaisesSyntaxError('with mock as None:\n  pass')
+        self.assertRaisesSyntaxError(
+            'with mock as (None):\n'
+            '  pass')
+
+    def testAssignmentToEmptyTupleError(self):
+        self.assertRaisesSyntaxError(
+            'with mock as ():\n'
+            '  pass')
+
+    def testAssignmentToTupleOnlyContainingNoneError(self):
+        self.assertRaisesSyntaxError('with mock as None,:\n  pass')
+        self.assertRaisesSyntaxError(
+            'with mock as (None,):\n'
+            '  pass')
+
+    def testAssignmentToTupleContainingNoneError(self):
+        self.assertRaisesSyntaxError(
+            'with mock as (foo, None, bar):\n'
+            '  pass')
+
+    def testContextThrows(self):
+        class ContextThrows(object):
+            def __context__(self):
+                raise RuntimeError("Context threw")
+
+        def shouldThrow():
+            ct = ContextThrows()
+            self.foo = None
+            with ct as self.foo:
+                pass
+        self.assertRaises(RuntimeError, shouldThrow)
+        self.assertEqual(self.foo, None)
+
+    def testEnterThrows(self):
+        class EnterThrows(object):
+            def __context__(self):
+                return self
+
+            def __enter__(self):
+                raise RuntimeError("Context threw")
+
+        def shouldThrow():
+            ct = EnterThrows()
+            self.foo = None
+            with ct as self.foo:
+                pass
+        self.assertRaises(RuntimeError, shouldThrow)
+        self.assertEqual(self.foo, None)
+
+    # We don't test throwing from __exit__ because that would be bad, m'kay?
+
+
+class ContextmanagerAssertionMixin(object):
+    TEST_EXCEPTION = RuntimeError("test exception")
+
+    def assertInWithManagerInvariants(self, mock_manager):
+        self.assertTrue(mock_manager.context_called)
+        self.assertTrue(mock_manager.enter_called)
+        self.assertFalse(mock_manager.exit_called)
+        self.assertEqual(mock_manager.exit_args, None)
+
+    def assertAfterWithManagerInvariants(self, mock_manager, exit_args):
+        self.assertTrue(mock_manager.context_called)
+        self.assertTrue(mock_manager.enter_called)
+        self.assertTrue(mock_manager.exit_called)
+        self.assertEqual(mock_manager.exit_args, exit_args)
+
+    def assertAfterWithManagerInvariantsNoError(self, mock_manager):
+        self.assertAfterWithManagerInvariants(mock_manager,
+            (None, None, None))
+
+    def assertInWithGeneratorInvariants(self, mock_generator):
+        self.assertTrue(mock_generator.yielded)
+        self.assertFalse(mock_generator.stopped)
+
+    def assertAfterWithGeneratorInvariantsNoError(self, mock_generator):
+        self.assertTrue(mock_generator.yielded)
+        self.assertTrue(mock_generator.stopped)
+
+    def raiseTestException(self):
+        raise self.TEST_EXCEPTION
+
+    def assertAfterWithManagerInvariantsWithError(self, mock_manager):
+        self.assertTrue(mock_manager.context_called)
+        self.assertTrue(mock_manager.enter_called)
+        self.assertTrue(mock_manager.exit_called)
+        self.assertEqual(mock_manager.exit_args[0], RuntimeError)
+        self.assertEqual(mock_manager.exit_args[1], self.TEST_EXCEPTION)
+
+    def assertAfterWithGeneratorInvariantsWithError(self, mock_generator):
+        self.assertTrue(mock_generator.yielded)
+        self.assertTrue(mock_generator.stopped)
+
+
+class NonexceptionalTestCase(unittest.TestCase, ContextmanagerAssertionMixin):
+    def testInlineGeneratorSyntax(self):
+        with mock_contextmanager_generator():
+            pass
+
+    def testUnboundGenerator(self):
+        mock = mock_contextmanager_generator()
+        with mock:
+            pass
+        self.assertAfterWithManagerInvariantsNoError(mock)
+
+    def testInlineGeneratorBoundSyntax(self):
+        with mock_contextmanager_generator() as foo:
+            self.assertInWithGeneratorInvariants(foo)
+        # FIXME: In the future, we'll try to keep the bound names from leaking
+        self.assertAfterWithGeneratorInvariantsNoError(foo)
+
+    def testInlineGeneratorBoundToExistingVariable(self):
+        foo = None
+        with mock_contextmanager_generator() as foo:
+            self.assertInWithGeneratorInvariants(foo)
+        self.assertAfterWithGeneratorInvariantsNoError(foo)
+
+    def testInlineGeneratorBoundToDottedVariable(self):
+        with mock_contextmanager_generator() as self.foo:
+            self.assertInWithGeneratorInvariants(self.foo)
+        self.assertAfterWithGeneratorInvariantsNoError(self.foo)
+
+    def testBoundGenerator(self):
+        mock = mock_contextmanager_generator()
+        with mock as foo:
+            self.assertInWithGeneratorInvariants(foo)
+            self.assertInWithManagerInvariants(mock)
+        self.assertAfterWithGeneratorInvariantsNoError(foo)
+        self.assertAfterWithManagerInvariantsNoError(mock)
+
+    def testNestedSingleStatements(self):
+        mock_a = mock_contextmanager_generator()
+        with mock_a as foo:
+            mock_b = mock_contextmanager_generator()
+            with mock_b as bar:
+                self.assertInWithManagerInvariants(mock_a)
+                self.assertInWithManagerInvariants(mock_b)
+                self.assertInWithGeneratorInvariants(foo)
+                self.assertInWithGeneratorInvariants(bar)
+            self.assertAfterWithManagerInvariantsNoError(mock_b)
+            self.assertAfterWithGeneratorInvariantsNoError(bar)
+            self.assertInWithManagerInvariants(mock_a)
+            self.assertInWithGeneratorInvariants(foo)
+        self.assertAfterWithManagerInvariantsNoError(mock_a)
+        self.assertAfterWithGeneratorInvariantsNoError(foo)
+
+
+class NestedNonexceptionalTestCase(unittest.TestCase,
+    ContextmanagerAssertionMixin):
+    def testSingleArgInlineGeneratorSyntax(self):
+        with nested(mock_contextmanager_generator()):
+            pass
+
+    def testSingleArgUnbound(self):
+        mock_contextmanager = mock_contextmanager_generator()
+        mock_nested = MockNested(mock_contextmanager)
+        with mock_nested:
+            self.assertInWithManagerInvariants(mock_contextmanager)
+            self.assertInWithManagerInvariants(mock_nested)
+        self.assertAfterWithManagerInvariantsNoError(mock_contextmanager)
+        self.assertAfterWithManagerInvariantsNoError(mock_nested)
+
+    def testSingleArgBoundToNonTuple(self):
+        m = mock_contextmanager_generator()
+        # This will bind all the arguments to nested() into a single list
+        # assigned to foo.
+        with nested(m) as foo:
+            self.assertInWithManagerInvariants(m)
+        self.assertAfterWithManagerInvariantsNoError(m)
+
+    def testSingleArgBoundToSingleElementParenthesizedList(self):
+        m = mock_contextmanager_generator()
+        # This will bind all the arguments to nested() into a single list
+        # assigned to foo.
+        # FIXME: what should this do:  with nested(m) as (foo,):
+        with nested(m) as (foo):
+            self.assertInWithManagerInvariants(m)
+        self.assertAfterWithManagerInvariantsNoError(m)
+
+    def testSingleArgBoundToMultipleElementTupleError(self):
+        def shouldThrowValueError():
+            with nested(mock_contextmanager_generator()) as (foo, bar):
+                pass
+        self.assertRaises(ValueError, shouldThrowValueError)
+
+    def testSingleArgUnbound(self):
+        mock_contextmanager = mock_contextmanager_generator()
+        mock_nested = MockNested(mock_contextmanager)
+        with mock_nested:
+            self.assertInWithManagerInvariants(mock_contextmanager)
+            self.assertInWithManagerInvariants(mock_nested)
+        self.assertAfterWithManagerInvariantsNoError(mock_contextmanager)
+        self.assertAfterWithManagerInvariantsNoError(mock_nested)
+
+    def testMultipleArgUnbound(self):
+        m = mock_contextmanager_generator()
+        n = mock_contextmanager_generator()
+        o = mock_contextmanager_generator()
+        mock_nested = MockNested(m, n, o)
+        with mock_nested:
+            self.assertInWithManagerInvariants(m)
+            self.assertInWithManagerInvariants(n)
+            self.assertInWithManagerInvariants(o)
+            self.assertInWithManagerInvariants(mock_nested)
+        self.assertAfterWithManagerInvariantsNoError(m)
+        self.assertAfterWithManagerInvariantsNoError(n)
+        self.assertAfterWithManagerInvariantsNoError(o)
+        self.assertAfterWithManagerInvariantsNoError(mock_nested)
+
+    def testMultipleArgBound(self):
+        mock_nested = MockNested(mock_contextmanager_generator(),
+            mock_contextmanager_generator(), mock_contextmanager_generator())
+        with mock_nested as (m, n, o):
+            self.assertInWithGeneratorInvariants(m)
+            self.assertInWithGeneratorInvariants(n)
+            self.assertInWithGeneratorInvariants(o)
+            self.assertInWithManagerInvariants(mock_nested)
+        self.assertAfterWithGeneratorInvariantsNoError(m)
+        self.assertAfterWithGeneratorInvariantsNoError(n)
+        self.assertAfterWithGeneratorInvariantsNoError(o)
+        self.assertAfterWithManagerInvariantsNoError(mock_nested)
+
+
+class ExceptionalTestCase(unittest.TestCase, ContextmanagerAssertionMixin):
+    def testSingleResource(self):
+        cm = mock_contextmanager_generator()
+        def shouldThrow():
+            with cm as self.resource:
+                self.assertInWithManagerInvariants(cm)
+                self.assertInWithGeneratorInvariants(self.resource)
+                self.raiseTestException()
+        self.assertRaises(RuntimeError, shouldThrow)
+        self.assertAfterWithManagerInvariantsWithError(cm)
+        self.assertAfterWithGeneratorInvariantsWithError(self.resource)
+
+    def testNestedSingleStatements(self):
+        mock_a = mock_contextmanager_generator()
+        mock_b = mock_contextmanager_generator()
+        def shouldThrow():
+            with mock_a as self.foo:
+                with mock_b as self.bar:
+                    self.assertInWithManagerInvariants(mock_a)
+                    self.assertInWithManagerInvariants(mock_b)
+                    self.assertInWithGeneratorInvariants(self.foo)
+                    self.assertInWithGeneratorInvariants(self.bar)
+                    self.raiseTestException()
+        self.assertRaises(RuntimeError, shouldThrow)
+        self.assertAfterWithManagerInvariantsWithError(mock_a)
+        self.assertAfterWithManagerInvariantsWithError(mock_b)
+        self.assertAfterWithGeneratorInvariantsWithError(self.foo)
+        self.assertAfterWithGeneratorInvariantsWithError(self.bar)
+
+    def testMultipleResourcesInSingleStatement(self):
+        cm_a = mock_contextmanager_generator()
+        cm_b = mock_contextmanager_generator()
+        mock_nested = MockNested(cm_a, cm_b)
+        def shouldThrow():
+            with mock_nested as (self.resource_a, self.resource_b):
+                self.assertInWithManagerInvariants(cm_a)
+                self.assertInWithManagerInvariants(cm_b)
+                self.assertInWithManagerInvariants(mock_nested)
+                self.assertInWithGeneratorInvariants(self.resource_a)
+                self.assertInWithGeneratorInvariants(self.resource_b)
+                self.raiseTestException()
+        self.assertRaises(RuntimeError, shouldThrow)
+        self.assertAfterWithManagerInvariantsWithError(cm_a)
+        self.assertAfterWithManagerInvariantsWithError(cm_b)
+        self.assertAfterWithManagerInvariantsWithError(mock_nested)
+        self.assertAfterWithGeneratorInvariantsWithError(self.resource_a)
+        self.assertAfterWithGeneratorInvariantsWithError(self.resource_b)
+
+    def testNestedExceptionBeforeInnerStatement(self):
+        mock_a = mock_contextmanager_generator()
+        mock_b = mock_contextmanager_generator()
+        self.bar = None
+        def shouldThrow():
+            with mock_a as self.foo:
+                self.assertInWithManagerInvariants(mock_a)
+                self.assertInWithGeneratorInvariants(self.foo)
+                self.raiseTestException()
+                with mock_b as self.bar:
+                    pass
+        self.assertRaises(RuntimeError, shouldThrow)
+        self.assertAfterWithManagerInvariantsWithError(mock_a)
+        self.assertAfterWithGeneratorInvariantsWithError(self.foo)
+
+        # The inner statement stuff should never have been touched
+        self.assertEqual(self.bar, None)
+        self.assertFalse(mock_b.context_called)
+        self.assertFalse(mock_b.enter_called)
+        self.assertFalse(mock_b.exit_called)
+        self.assertEqual(mock_b.exit_args, None)
+
+    def testNestedExceptionAfterInnerStatement(self):
+        mock_a = mock_contextmanager_generator()
+        mock_b = mock_contextmanager_generator()
+        def shouldThrow():
+            with mock_a as self.foo:
+                with mock_b as self.bar:
+                    self.assertInWithManagerInvariants(mock_a)
+                    self.assertInWithManagerInvariants(mock_b)
+                    self.assertInWithGeneratorInvariants(self.foo)
+                    self.assertInWithGeneratorInvariants(self.bar)
+                self.raiseTestException()
+        self.assertRaises(RuntimeError, shouldThrow)
+        self.assertAfterWithManagerInvariantsWithError(mock_a)
+        self.assertAfterWithManagerInvariantsNoError(mock_b)
+        self.assertAfterWithGeneratorInvariantsWithError(self.foo)
+        self.assertAfterWithGeneratorInvariantsNoError(self.bar)
+
+
+def test_main():
+    run_unittest(FailureTestCase, NonexceptionalTestCase,
+                 NestedNonexceptionalTestCase, ExceptionalTestCase)
+
+
+if __name__ == '__main__':
+    test_main()
+