You are reading an old version of the documentation (v2.2.2). For the latest version see https://matplotlib.org/stable/api/_as_gen/matplotlib.axes.Axes.set_facecolor.html
Version 2.2.2
matplotlib
Fork me on GitHub

matplotlib.axes.Axes.set_facecolor

Axes.set_facecolor(color)

Set the Axes facecolor.

Parameters:
color : color