“UserWarning: Matplotlib is currently using agg, which is a non-GUI backend, so cannot show the figure.” when plotting figure with pyplot on Pycharm

Question

I am trying to plot a simple graph using pyplot, e.g.:

import matplotlib.pyplot as plt
plt.plot([1,2,3],[5,7,4])
plt.show()

but the figure

Answer 1

When I ran into this error on Spyder, I changed from running my code line by line to highlighting my block of plotting code and running that all at once. Voila, the image appeared.