如何重新排序CSV文件的行？

import csv
import operator

# 读取CSV文件
def read_csv(file_name):
    with open(file_name, newline='') as csvfile:
        reader = csv.DictReader(csvfile)
        data = [row for row in reader]
    return data

# 写入CSV文件
def write_csv(file_name, fieldnames, data):
    with open(file_name, 'w', newline='') as csvfile:
        writer = csv.DictWriter(csvfile, fieldnames=fieldnames)
        writer.writeheader()
        for row in data:
            writer.writerow(row)

# 主函数
def main(input_file, output_file, sort_column):
    # 读取数据
    data = read_csv(input_file)
    
    # 按指定列排序
    sorted_data = sorted(data, key=operator.itemgetter(sort_column))
    
    # 获取字段名
    fieldnames = data[0].keys()
    
    # 写入排序后的数据
    write_csv(output_file, fieldnames, sorted_data)

# 使用示例
input_file = 'input.csv'
output_file = 'output.csv'
sort_column = 'column_name'  # 替换为实际列名
main(input_file, output_file, sort_column)