Is anyone aware of a well-maintained, simple, cross-platform python package that can play a numpy array as sound over speakers? 

I am aware of https://wiki.python.org/moin/Audio/.  However, in all the cases there, as far as I can find they either do not support numpy arrays, are not cross-platform, cannot playback sound at all, or are unmaintained.  There is also PySoundCard, which would do what I need but also appears to be unmaintained (no release in over a year, and no commits in 5 months, no release with serious bugfixes mentioned in commits).