:returns: A list of function matches that appear to differ

def differing_functions(self):
        """
        :returns: A list of function matches that appear to differ
        """
        different_funcs = []
        for (func_a, func_b) in self.function_matches:
            if not self.functions_probably_identical(func_a, func_b):
                different_funcs.append((func_a, func_b))
        return different_funcs