如何使用子进程保存python文件的输出，并将所有输出附加到一个文件中？

import subprocess

def save_output_to_file(file_path, command):
    with open(file_path, 'a') as file:
        process = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, shell=True)
        while True:
            output = process.stdout.readline()
            if output == b'' and process.poll() is not None:
                break
            if output:
                file.write(output.decode('utf-8'))
                file.flush()

# 示例用法
save_output_to_file('output.txt', 'python your_script.py')