如何在Matplotlib中显示顶部和底部5个行值以及自定义行值？

import matplotlib.pyplot as plt
import numpy as np

x = np.arange(1, 11)
y = np.random.randint(1, 20, size=10)

plt.bar(x, y)

top_values = sorted(zip(x, y), key=lambda x: x[1], reverse=True)[:5]
bottom_values = sorted(zip(x, y), key=lambda x: x[1])[:5]

for i, (value_x, value_y) in enumerate(top_values):
    plt.text(value_x, value_y, str(value_y), ha='center', va='bottom')

for i, (value_x, value_y) in enumerate(bottom_values):
    plt.text(value_x, value_y, str(value_y), ha='center', va='top')

custom_values = [(3, 15), (7, 18), (9, 12)]
for value_x, value_y in custom_values:
    plt.text(value_x, value_y, str(value_y), ha='center', va='bottom')

plt.show()