+= append class operator

[schwehr at gmail.com]

Hi All,

This is probably a FAQ, but is there an operator mapping for += for
classes?  Or does a += b get converted to a = a + b?  I would like to
make this operator faster for the BitVector class, but I don't see +=
in http://docs.python.org/lib/operator-map.html

I could always create an append method, but += is nice and concise.

Thanks,
-kurt