Bizarre additional calling overhead.

[Chris Mellon]

>>> def test_func():
...     pass
...
>>> import new
>>> test_func2 = new.function(test_func.func_code, {}, "test_func2")
>>> test_func2
<function test_func2 at 0x01B8C2F0>
>>> test_func
<function test_func at 0x01B8C270>
>>> import timeit
>>> tf = timeit.Timer("test_func()", "from __main__ import test_func")
>>> tf.repeat()
[0.2183461704377247, 0.18068215314489791, 0.17978585841498085]
>>> tf2 = timeit.Timer("test_func2()", "from __main__ import test_func2")
>>> tf2.repeat()
[0.40015390239890891, 0.35893452879396648, 0.36034628133737456]
>>>

Why almost twice the calling overhead for a dynamic function?