How do I format axis number format to thousands with a comma in matplotlib?

Question

How can I change the format of the numbers in the x-axis to be like 10,000 instead of 10000? Ideally, I would just like to do something like this:<

Answer 1

Short answer without importing matplotlib as mpl

plt.gca().yaxis.set_major_formatter(plt.matplotlib.ticker.StrMethodFormatter('{x:,.0f}'))

Modified from @AlexG's answer