How to get the parents of a Python class?

Use the following attribute:

cls.__bases__

From the docs:

The tuple of base classes of a class object.

Example:

>>> str.__bases__
(<type 'basestring'>,)

Another example:

>>> class A(object):
...   pass
... 
>>> class B(object):
...   pass
... 
>>> class C(A, B):
...   pass
... 
>>> C.__bases__
(<class '__main__.A'>, <class '__main__.B'>)

If you want all the ancestors rather than just the immediate ones, use inspect.getmro:

import inspect
print inspect.getmro(cls)

Usefully, this gives you all ancestor classes in the "method resolution order" -- i.e. the order in which the ancestors will be checked when resolving a method (or, actually, any other attribute -- methods and other attributes live in the same namespace in Python, after all;-).