BrokenMethodImplementation "doesn't allow enough arguments" error when using staticmethods on Python 3

[rouge8]

Verifying a class using @provider behaves differently on Python 2.7 vs. Python 3.7 with zope.interface 4.5.0:

import zope.interface
from zope.interface.verify import verifyObject

class IFoo(zope.interface.Interface):
    def bar(a, b):
        pass

@zope.interface.provider(IFoo)
class Foo(object):
    @staticmethod
    def bar(a, b):
        pass

assert verifyObject(IFoo, Foo)

On Python 2.7, this code passes. On Python 3.7 it raises a BrokenMethodImplementation:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/andy/test/.tox/py37/lib/python3.7/site-packages/zope/interface/verify.py", line 105, in verifyObject
    return _verify(iface, candidate, tentative, vtype='o')
  File "/Users/andy/test/.tox/py37/lib/python3.7/site-packages/zope/interface/verify.py", line 97, in _verify
    raise BrokenMethodImplementation(name, mess)
zope.interface.exceptions.BrokenMethodImplementation: The implementation of bar violates its contract
        because implementation doesn't allow enough arguments.