如何按pandas的结果显示每日直方图？

import pandas as pd
import matplotlib.pyplot as plt

data = {'日期': ['2022-01-01', '2022-01-02', '2022-01-03', '2022-01-04', '2022-01-05'],
        '数值': [10, 15, 8, 12, 20]}
df = pd.DataFrame(data)

df['日期'] = pd.to_datetime(df['日期'])

df.set_index('日期', inplace=True)

daily_counts = df.groupby(pd.Grouper(freq='D')).count()

daily_counts.plot(kind='bar', figsize=(10, 6))
plt.xlabel('日期')
plt.ylabel('频数')
plt.title('每日直方图')
plt.show()