Comment 2 for bug 903444

StacktraceTop:
 g_type_get_qdata (type=<optimized out>, quark=55) at /build/buildd/glib2.0-2.31.2/./gobject/gtype.c:3681
 pygobject_lookup_class (gtype=0) at /build/buildd/pygobject-2-2.28.6/gobject/pygobject.c:905
 pygobject_lookup_class (gtype=0) at /build/buildd/pygobject-2-2.28.6/gobject/pygobject.c:894
 pyg_type_get_bases (gtype=0) at /build/buildd/pygobject-2-2.28.6/gobject/pygobject.c:659
 pygobject_new_with_interfaces (gtype=0) at /build/buildd/pygobject-2-2.28.6/gobject/pygobject.c:702