diff -r be3874cf87f3 Lib/test/test_tools/test_unparse.py
--- a/Lib/test/test_tools/test_unparse.py	Sat Mar 05 14:05:45 2016 +0200
+++ b/Lib/test/test_tools/test_unparse.py	Sat Mar 05 16:54:42 2016 -0500
@@ -134,6 +134,11 @@
 class UnparseTestCase(ASTTestCase):
     # Tests for specific bugs found in earlier versions of unparse
 
+    def test_dict_unpacking_in_dict(self):
+        "for dictionary unpacking operator in dicts e.g. {**{'y': 2}}, PEP 448"
+        self.check_roundtrip(r"""{**{'y': 2}, 'x': 1}""")
+        self.check_roundtrip(r"""{**{'y': 2}, **{'x': 1}}""")
+
     def test_fstrings(self):
         # See issue 25180
         self.check_roundtrip(r"""f'{f"{0}"*3}'""")
diff -r be3874cf87f3 Tools/parser/unparse.py
--- a/Tools/parser/unparse.py	Sat Mar 05 14:05:45 2016 +0200
+++ b/Tools/parser/unparse.py	Sat Mar 05 16:54:42 2016 -0500
@@ -456,12 +456,18 @@
 
     def _Dict(self, t):
         self.write("{")
-        def write_pair(pair):
-            (k, v) = pair
+        def write_key_value_pair(k,v):
             self.dispatch(k)
             self.write(": ")
             self.dispatch(v)
-        interleave(lambda: self.write(", "), write_pair, zip(t.keys, t.values))
+        def write_item(item):
+            (k, v) = item
+            if k is None: # for dictionary unpacking operator in dicts  {**{'y': 2}}, PEP 448
+                self.write("**")
+                self.dispatch(v)
+            else:
+                write_key_value_pair(k,v)
+        interleave(lambda: self.write(", "), write_item, zip(t.keys, t.values))
         self.write("}")
 
     def _Tuple(self, t):