Change Matplotlib backend to avoid QT5 issues.

This is an issue that has been bugging me for about 5 hours. Until I reached the solution of changing the backend of Matplotlib for good.

import matplotlib
gui_env = ['TKAgg','GTKAgg','Qt4Agg','WXAgg']
for gui in gui_env:
    try:
        print "testing", gui
        matplotlib.use(gui,warn=False, force=True)
        from matplotlib import pyplot as plt
        break
    except:
        continue
print "Using:",matplotlib.get_backend()

Credits: https://stackoverflow.com/a/43015816/1928610