Speed-up named tuple's _make() constructor.

Lib/collections.py

@@ -65,9 +65,9 @@ def namedtuple(typename, field_names, verbose=False):
         def __new__(cls, %(argtxt)s):
             return tuple.__new__(cls, (%(argtxt)s)) \n
         @classmethod
-        def _make(cls, iterable):
+        def _make(cls, iterable, new=tuple.__new__, len=len):
             'Make a new %(typename)s object from a sequence or iterable'
-            result = tuple.__new__(cls, iterable)
+            result = new(cls, iterable)
             if len(result) != %(numfields)d:
                 raise TypeError('Expected %(numfields)d arguments, got %%d' %% len(result))
             return result \n