diff -r 9ea84f006892 Lib/argparse.py
--- a/Lib/argparse.py	Wed May 01 15:15:50 2013 +0200
+++ b/Lib/argparse.py	Tue Jul 02 23:12:01 2013 -0700
@@ -467,7 +467,8 @@
         text = _re.sub(r'(%s) ' % open, r'\1', text)
         text = _re.sub(r' (%s)' % close, r'\1', text)
         text = _re.sub(r'%s *%s' % (open, close), r'', text)
-        text = _re.sub(r'\(([^|]*)\)', r'\1', text)
+        # text = _re.sub(r'\(([^|]*)\)', r'\1', text)
+        text = _re.sub(r'( )\(([^|]*)\)', r'\1\2', text)
         text = text.strip()
 
         # return the text
diff -r 9ea84f006892 Lib/test/test_argparse.py
--- a/Lib/test/test_argparse.py	Wed May 01 15:15:50 2013 +0200
+++ b/Lib/test/test_argparse.py	Tue Jul 02 23:12:01 2013 -0700
@@ -4885,6 +4885,45 @@
     def test_nargs_3_metavar_length3(self):
         self.do_test_no_exception(nargs=3, metavar=("1", "2", "3"))
 
+# ==========================
+# metavar with ()
+# ==========================
+
+class TestMetavarWithParen(TestCase):
+    "MutuallyExclusiveGroup trimming should not remove () from metavars"
+    def test_default_formatting(self):
+        "default usage with expanded range of choices"
+        full = r"\[-h\] \[--foo {0,1,2,3,4,5,6,7,8,9}\]\n"
+        parser = ErrorRaisingArgumentParser()
+        parser.add_argument("--foo", type=int, choices=range(10))
+        cm = parser.format_usage()
+        self.assertRegex(cm, full)
+
+    def test_format_with_metavar(self):
+        "usage with metavar"
+        parser = ErrorRaisingArgumentParser()
+        parser.add_argument("--foo", type=int, choices=range(20), metavar='range:20')
+        cm = parser.format_usage()
+        self.assertRegex(cm, r'usage: (.*) \[\-h\] \[--foo range:20\]\n')
+
+    def test_format_with_paren(self):
+        "usage with a metavar that include ()"
+        parser = ErrorRaisingArgumentParser()
+        parser.add_argument("--foo", type=int, choices=range(20), metavar='range(0,20)')
+        cm = parser.format_usage()
+        self.assertRegex(cm, r'usage: (.*) \[-h\] \[--foo range\(0,20\)\]\n')
+
+    def test_format_with_paren(self):
+        "metavar has no effect on the choices error message - yet"
+        parser = ErrorRaisingArgumentParser()
+        parser.add_argument("--foo", type=int, choices=range(20), metavar='range(0,20)')
+        self.assertEqual(parser.parse_args(['--foo','1']), NS(foo=1))
+        with self.assertRaises(ArgumentParserError) as cm:
+            parser.parse_args(['--foo','21'])
+        msg = str(cm.exception)
+        self.assertRegex(msg, 'invalid choice')
+        self.assertNotIn(msg, 'range\(0,20\)')
+
 # ============================
 # from argparse import * tests
 # ============================