将所有匹配的行移到某个字符串的第一个匹配项后面

apple
banana
apple
orange
apple

import re

# 读取文件内容
with open('example.txt', 'r') as file:
    lines = file.readlines()

# 找到第一个匹配项的索引
first_match_index = None
for i, line in enumerate(lines):
    if 'apple' in line:
        first_match_index = i
        break

if first_match_index is not None:
    # 收集所有匹配项
    matches = [line for line in lines if 'apple' in line]
    # 移除原文件中的所有匹配项
    lines = [line for line in lines if 'apple' not in line]
    # 将匹配项插入到第一个匹配项后面
    lines[first_match_index:first_match_index] = matches

# 写回文件
with open('example.txt', 'w') as file:
    file.writelines(lines)