Matplotlib.axes.Axes.grid() in Python

# Implementation of matplotlib function   
import matplotlib.pyplot as plt
import numpy as np
   
fig, ax = plt.subplots()
ax.plot([1, 2, 3])
ax.grid()
ax.set_title('matplotlib.axes.Axes.grid() Example\n',
             fontsize = 12, fontweight ='bold')
plt.show()

# Implementation of matplotlib function
import numpy as np
import matplotlib.pyplot as plt
  
x = np.arange(-5, 5, 0.01)
y1 = -3 * x*x + 10 * x + 10
y2 = 3 * x*x + x
  
fig, [ax, ax1] = plt.subplots(2, 1, 
                              sharex = True)
ax.plot(x, y1, x, y2, color ='black')
ax.fill_between(x, y1, y2, where = y2 >y1,
                facecolor ='green',
                alpha = 0.8)
ax.fill_between(x, y1, y2, where = y2 <= y1, 
                facecolor ='black', 
                alpha = 0.8)
ax.xaxis.grid(True, color ="black")
ax.set_title('matplotlib.axes.Axes.grid() \
Example\n\n Grid in X-axis',
             fontsize = 12, fontweight ='bold')
ax1.plot(x, y1, x, y2, color ='black')
ax1.fill_between(x, y1, y2, where = y2 >y1, 
                 facecolor ='green',
                 alpha = 0.8)
ax1.fill_between(x, y1, y2, where = y2 <= y1,
                 facecolor ='black', 
                 alpha = 0.8)
ax1.yaxis.grid(True, color ="black")
ax1.set_title('Grid in y-axis',
             fontsize = 12, fontweight ='bold')
plt.show()