Make filled polygons between two curves in Python using Matplotlib

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Matplotlib is an amazing visualization library in Python for 2D plots of arrays. Matplotlib is a multi-platform data visualization library built on NumPy arrays and designed to work with the broader SciPy stack.
To create filled polygons between two curves a PolyCollection filling needs to be created between y1 and y2.
Parameters for the above task:

x: It is an array of length N that holds data of x.
y1: It is an array or a scalar of length N that holds data of y.
y2:It is an array or a scalar of length N that holds data of y.

Example:

Python3

import matplotlib.pyplot as plt
import numpy as np
# set the width 
width = 3.5
 
# set the height
height = 2.5
 
# set the depth
depth = 65
 
# plot the figure
plt.figure(figsize =(width, height), dpi = depth)
 
# set the x array of length 3
x = [1, 3, 6]
 
# set y1 array of length 3
y1 = [2, 3.5, 4]
 
# set y2 array of length 3
y2 = [3, 4, 5.5]
 
# fill the horizontal area between y1 and y2
plt.fill_between(x, y1, y2)
 
# show the plotted figure
plt.show()