如何使用pandas从数据帧绘制(分组的)条形图

import pandas as pd
import matplotlib.pyplot as plt

data = {'Group': ['A', 'A', 'B', 'B', 'C', 'C'],
        'Category': ['X', 'Y', 'X', 'Y', 'X', 'Y'],
        'Value': [10, 15, 7, 12, 9, 5]}
df = pd.DataFrame(data)

grouped = df.groupby(['Group', 'Category']).sum().reset_index()

pivot_df = grouped.pivot(index='Group', columns='Category', values='Value')

pivot_df.plot(kind='bar')
plt.xlabel('Group')
plt.ylabel('Value')
plt.title('Grouped Bar Chart')
plt.legend(title='Category')
plt.show()