Check for bound/unbound class method (python2.7)

py27_bound_unbound_method.txt

# class for autopsy

In [1]: class A:
   ...:     def foo():
   ...:         pass


# initial investigations

In [16]: str(A.foo)
Out[16]: '<unbound method A.foo>'

In [17]: str(A().foo)
Out[17]: '<bound method A.foo of <__main__.A instance at 0x7fb8508eb830>>'


# Open CPython code, look for strings "<bound method" and "<unbound method"
# https://github.com/python/cpython/blob/2.7/Objects/classobject.c#L2415

# Bingo! check im_self propert of the method

In [29]: A.foo.im_self is None
Out[29]: True

In [31]: A().foo.im_self
Out[31]: <__main__.A instance at 0x7fb850936098

In [30]: A().foo.im_self  is None
Out[30]: False