Trying to fix Issue #171

I tried to fix issue #171 and I also added a line ``$(LLVM_CONFIGURE_LINE) --disable-bindings`` in Makefile because if I don't have ``-disable-bindings`` flag, I won't be able to configure LLVM properly, there is an error saying since I have enabled bindings then I must install ctypes on my machine, which I have installed.

Back to bug #171, I tried to add some simple identity testing in ``__contains__`` and __eq__`` method. But I don't know for sure this is sufficient. I wonder should what does ``compareInternal`` do exactly? Should we put the identity test there?

Also, this is my first pull request, I have signed the agreement. Thanks!