how to check if y axis is inverted matplotlib

import matplotlib.pyplot as plt

# ('gca' stands for get current axes)

# To check whether the y axis is inverted:
plt.gca().yaxis_inverted()

# To check whether the x axis is inverted:
plt.gca().xaxis_inverted()

"""

Both functions return True if their axes are inverted.
- The y axis is inverted if the values are increasing downwards.
- The x axis is inverted if the values are increasing leftwards.

"""

# To flip the y axis:
plt.gca().invert_yaxis()

#To flip the x axis:
plt.gca().invert_xaxis()

"""

When plotting the equation 'y=-x' the y axis tends to flip for some
reason, so to overcome this and keep the y axis non-inverted you can
check whether the axis is inverted and if True re-flip it the right way
round:

"""

if plt.gca().yaxis_inverted():
    plt.gca().invert_yaxis()