python2, matplotlib, 2d plot on 3d plot, bug hunting, ValueError Unknown projection '3d'

Traceback (most recent call last):
self, *args, **kwargs)
File "/usr/lib/python2.7/dist-packages/matplotlib/projections/__init__.py", line 98, in process_projection_requirements
projection_class = get_projection_class(projection)
File "/usr/lib/python2.7/dist-packages/matplotlib/projections/__init__.py", line 67, in get_projection_class
raise ValueError("Unknown projection '%s'" % projection)
ValueError: Unknown projection '3d'