Factor out some duplication.
Factor out some duplication.

* python/libvir.c (VIR_PY_NONE): New macro, to encapsulate
a common two-statement sequence.
Replace all such 2-stmt sequences.

libvirt/libvirt-python,libvirt/libvirt-python,cardoe/libvirt-python,cardoe/libvirt-python,cardoe/libvirt-python,libvirt/libvirt-python