Plotly:如何为离散的分类变量设置choropleth图的颜色？

import plotly.express as px
import pandas as pd

# 创建示例数据
data = pd.DataFrame({
    'Country': ['China', 'USA', 'Germany', 'Japan'],
    'Category': ['A', 'B', 'C', 'A']
})

# 将分类变量映射为整数编码
data['Category_Code'] = pd.factorize(data['Category'])[0]

# 创建choropleth图
fig = px.choropleth(data_frame=data,
                    locations='Country',
                    locationmode='country names',
                    color='Category_Code',
                    color_continuous_scale=['red', 'green', 'blue'],
                    labels={'Category_Code': 'Category'},
                    title='Choropleth Map')

# 显示图表
fig.show()