Bug report
The repr of partialmethod object contains redundant commas and spaces. Compare it with the repr of partial:
>>> import functools >>> def test(*args, **kwargs): pass ... >>> functools.partial(test) functools.partial(<function test at 0x7fcbe91819d0>) >>> functools.partial(test, a=1) functools.partial(<function test at 0x7fcbe91819d0>, a=1) >>> functools.partialmethod(test) functools.partialmethod(<function test at 0x7fcbe91819d0>, , ) >>> functools.partialmethod(test, a=1) functools.partialmethod(<function test at 0x7fcbe91819d0>, , a=1)