Sometimes I can't pickle figures.

Works:

• fig = plt.gcf(), pickle.dump(fig, file, pickle.HIGHEST_PROTOCOL)

Does not work:

• fig = plt.figure(), pickle.dump(fig, file, pickle.HIGHEST_PROTOCOL)
• fig, ax = plt.subplots(), pickle.dump(fig, file, pickle.HIGHEST_PROTOCOL)

I also loaded a pickled figure and changed some things and it wouldn't pickle either.

Matplotlib 1.5.1 via pip
Python 2.7.6 in virtualenv
Linux