Can I create an object class with some methods implemented in C and others in Python (e.g. through inheritance)?
In earlier versions, C objects are created by factory functions, and cannot be directly inherited. You can get around by using a Python class as a facade, and delegate to an internal C object as necessary.
The Boost Python Library (BPL, http://www.boost.org/libs/python/doc/index.html) provides a way of doing this from C++ (i.e. you can inherit from an extension class written in C++ using the BPL).