Matplotlib.axes.Axes.fill() in Python

# Implementation of matplotlib function
     
import numpy as np
from matplotlib import patches
import matplotlib.pyplot as plt
 
x = np.array([1, 4, 1, 4])
y = np.array([1, 1, 4, 4])

fig, ax1 = plt.subplots()
ax1.fill(x, y, facecolor ='green')
ax1.set_title('matplotlib.axes.Axes.fill Example 1')
plt.show()

# Implementation of matplotlib function
     
import numpy as np
from matplotlib import patches
import matplotlib.pyplot as plt
 
theta = np.deg2rad(np.arange(0.0, 360.0, 1.0))
x = 0.5 * np.cos(theta)
y = 0.5 * np.sin(theta)

fig, (ax1, ax2, ax3) = plt.subplots(1, 3, figsize =(9, 3),
                                    subplot_kw ={'aspect': 'equal'},
                                    sharey = True)
ax1.fill(x, y, facecolor ='green')
ax1.set_title('Fig 1')

ax2.fill(x, y, facecolor ='green', edgecolor ='black',
         linewidth = 4)

ax2.set_title('Fig 2')

ax3.fill(x, y, facecolor ='none', edgecolor ='green', 
         linewidth = 4)
ax3.set_title('Fig 3')

plt.show()