Python/ctypes: fixed storage of graph callbacks.
Python/ctypes: fixed storage of graph callbacks.

libmapper/libmapper,radarsat1/libmapper,libmapper/libmapper,radarsat1/libmapper,malloch/libmapper,malloch/libmapper,radarsat1/libmapper,malloch/libmapper,malloch/libmapper,libmapper/libmapper,radarsat1/libmapper,libmapper/libmapper,radarsat1/libmapper,libmapper/libmapper,malloch/libmapper,malloch/libmapper,libmapper/libmapper