I am not sure why they use fig,ax = plt.subplots() [duplicate]

I understood simple concepts about comma operator in Python. For instance,

x0, sigma = 0, 0.1

means x0 = 0 and sigma = 0.1. But I obtained some code that has a line that looks like the following,

y, xe = np.histogram(np.random.normal(x0, sigma, 1000))

where the output of y and xe are the following:

y Out[10]: array([ 3, 17, 58, 136, 216, 258, 189, 87, 31, 5], dtype=int64) xe Out[11]: array([-0.33771565, -0.27400243, -0.21028922, -0.146576 , -0.08286279, -0.01914957, 0.04456364, 0.10827686, 0.17199007, 0.23570329, 0.2994165 ])

I am not sure how to read the y, xe expression. What could I look up to understand what it's saying?