如何根据csv中给定的字典更改列的值？

import csv

def update_csv_column(csv_file, column_name, value_dict):
    # 读取CSV文件
    with open(csv_file, 'r') as file:
        reader = csv.DictReader(file)
        rows = list(reader)

    # 更新列的值
    for row in rows:
        if row[column_name] in value_dict:
            row[column_name] = value_dict[row[column_name]]

    # 写入更新后的数据到CSV文件
    with open(csv_file, 'w', newline='') as file:
        writer = csv.DictWriter(file, fieldnames=reader.fieldnames)
        writer.writeheader()
        writer.writerows(rows)

# 示例用法
csv_file = 'data.csv'  # CSV文件路径
column_name = 'category'  # 要更改的列名
value_dict = {'A': 'Category A', 'B': 'Category B'}  # 给定的字典，用于更新列的值

update_csv_column(csv_file, column_name, value_dict)