有没有办法在.txt文件中搜索一个键并在Python3.7中更新它的值？

file = open('file.txt', 'r+')

lines = file.readlines()

target_key = 'your_key'
new_value = 'your_new_value'

for i in range(len(lines)):
    key_value = lines[i].split('=')
    if key_value[0].strip() == target_key:
        lines[i] = f'{target_key} = {new_value}\n'
        break

file.seek(0)
file.writelines(lines)

file.close()

target_key = 'your_key'
new_value = 'your_new_value'

with open('file.txt', 'r+') as file:
    lines = file.readlines()

    for i in range(len(lines)):
        key_value = lines[i].split('=')
        if key_value[0].strip() == target_key:
            lines[i] = f'{target_key} = {new_value}\n'
            break

    file.seek(0)
    file.writelines(lines)