diff -r 421847aa0b22 Lib/argparse.py
--- a/Lib/argparse.py	Mon Jun 01 19:38:50 2015 -0700
+++ b/Lib/argparse.py	Mon Jun 01 22:19:47 2015 -0700
@@ -118,10 +118,16 @@
     def __repr__(self):
         type_name = type(self).__name__
         arg_strings = []
+        star_args={}
         for arg in self._get_args():
             arg_strings.append(repr(arg))
         for name, value in self._get_kwargs():
-            arg_strings.append('%s=%r' % (name, value))
+            if name.isidentifier():
+                arg_strings.append('%s=%r' % (name, value))
+            else:
+                star_args[name] = value
+        if star_args:
+            arg_strings.append('**%s' %(repr(star_args)))
         return '%s(%s)' % (type_name, ', '.join(arg_strings))
 
     def _get_kwargs(self):
diff -r 421847aa0b22 Lib/test/test_argparse.py
--- a/Lib/test/test_argparse.py	Mon Jun 01 19:38:50 2015 -0700
+++ b/Lib/test/test_argparse.py	Mon Jun 01 22:19:47 2015 -0700
@@ -4511,6 +4511,21 @@
         ns = argparse.Namespace(foo=42, bar='spam')
         string = "Namespace(bar='spam', foo=42)"
         self.assertStringEqual(ns, string)
+    
+    def test_namespace_starkwargs_notidentifier(self):
+        ns = argparse.Namespace(**{'"': 'quote'})
+        string = '''Namespace(**{'"': 'quote'})'''
+        self.assertStringEqual(ns, string)
+
+    def test_namespace_kwargs_and_starkwargs_notidentifier(self):
+        ns = argparse.Namespace(a=1, **{'"': 'quote'})
+        string = '''Namespace(a=1, **{'"': 'quote'})'''
+        self.assertStringEqual(ns, string)
+
+    def test_namespace_starkwargs_identifier(self):
+        ns = argparse.Namespace(**{'valid': True})
+        string = 'Namespace(valid=True)'
+        self.assertStringEqual(ns, string)
 
     def test_parser(self):
         parser = argparse.ArgumentParser(prog='PROG')