You are reading an old version of the documentation (v2.2.4). For the latest version see https://matplotlib.org/stable/api/_as_gen/matplotlib.axes.Axes.get_shared_y_axes.html
Version 2.2.4
matplotlib
Fork me on GitHub

matplotlib.axes.Axes.get_shared_y_axes

Axes.get_shared_y_axes()

Return a reference to the shared axes Grouper object for y axes.