diff -r 3b94a4ef244e Lib/test/test_decimal.py
--- a/Lib/test/test_decimal.py	Fri Feb 07 17:53:13 2014 +0100
+++ b/Lib/test/test_decimal.py	Fri Feb 07 22:18:31 2014 +0200
@@ -753,7 +753,7 @@
         for v in [-2**63-1, -2**63, -2**31-1, -2**31, 0,
                    2**31-1, 2**31, 2**63-1, 2**63]:
             d = nc.create_decimal(v)
-            self.assertTrue(isinstance(d, Decimal))
+            self.assertIsInstance(d, Decimal)
             self.assertEqual(int(d), v)
 
         nc.prec = 3
@@ -4299,34 +4299,40 @@
             self.assertEqual(r, Decimal('194'))
 
             q, r = divmod(Decimal("NaN"), 7)
-            self.assertTrue(q.is_nan() and r.is_nan())
+            self.assertTrue(q.is_nan())
+            self.assertTrue(r.is_nan())
 
             c.traps[InvalidOperation] = False
             q, r = divmod(Decimal("NaN"), 7)
-            self.assertTrue(q.is_nan() and r.is_nan())
+            self.assertTrue(q.is_nan())
+            self.assertTrue(r.is_nan())
 
             c.traps[InvalidOperation] = False
             c.clear_flags()
             q, r = divmod(Decimal("inf"), Decimal("inf"))
-            self.assertTrue(q.is_nan() and r.is_nan())
+            self.assertTrue(q.is_nan())
+            self.assertTrue(r.is_nan())
             self.assertTrue(c.flags[InvalidOperation])
 
             c.clear_flags()
             q, r = divmod(Decimal("inf"), 101)
-            self.assertTrue(q.is_infinite() and r.is_nan())
+            self.assertTrue(q.is_infinite())
+            self.assertTrue(r.is_nan())
             self.assertTrue(c.flags[InvalidOperation])
 
             c.clear_flags()
             q, r = divmod(Decimal(0), 0)
-            self.assertTrue(q.is_nan() and r.is_nan())
+            self.assertTrue(q.is_nan())
+            self.assertTrue(r.is_nan())
             self.assertTrue(c.flags[InvalidOperation])
 
             c.traps[DivisionByZero] = False
             c.clear_flags()
             q, r = divmod(Decimal(11), 0)
-            self.assertTrue(q.is_infinite() and r.is_nan())
-            self.assertTrue(c.flags[InvalidOperation] and
-                            c.flags[DivisionByZero])
+            self.assertTrue(q.is_infinite())
+            self.assertTrue(r.is_nan())
+            self.assertTrue(c.flags[InvalidOperation])
+            self.assertTrue(c.flags[DivisionByZero])
 
     def test_power(self):
         Decimal = self.decimal.Decimal
@@ -5160,7 +5166,7 @@
         c = DefaultContext.copy()
 
         # Signal dict methods
-        self.assertTrue(Overflow in c.traps)
+        self.assertIn(Overflow, c.traps)
         c.clear_traps()
         for k in c.traps.keys():
             c.traps[k] = True
@@ -5171,7 +5177,7 @@
             self.assertFalse(v)
 
         self.assertFalse(c.flags.get(Overflow))
-        self.assertIs(c.flags.get("x"), None)
+        self.assertIsNone(c.flags.get("x"))
         self.assertEqual(c.flags.get("x", "y"), "y")
         self.assertRaises(TypeError, c.flags.get, "x", "y", "z")