If they are not C specific they should be moved to the base class (TestHeap).  TestHeapC and TestHeapPython should contain only tests specific to the C and Python versions respectively.

The goal here is to make sure that they are run once with the Python version, and again with the C version -- but only if the C version is available.
Currently, if _heapq is missing, the C tests (i.e. TestHeapC) are run anyway using the Python module, when instead they should be skipped.

c_heapq = import_fresh_module('heapq', fresh=['_heapq']) should be fixed to try to import _heapq and return None if the import fails, so that a @skipUnless(c_heapq, 'test requires the _heapq module') decorator can be added to TestHeapC.
See also http://www.python.org/dev/peps/pep-0399/

This can be fixed in 2.7 first.