int_pow():  Repair typo when passing on to float pow (the 2nd argument was being passed as both the 2nd and 3rd args).  Regression test will follow.
int_pow():  Repair typo when passing on to float pow (the 2nd argument was
being passed as both the 2nd and 3rd args).  Regression test will follow.

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator