如何匹配给定字符串中的特定行

import re

def match_specific_lines(string, pattern):
    lines = string.split('\n')
    matched_lines = []
    for line in lines:
        if re.match(pattern, line):
            matched_lines.append(line)
    return matched_lines

# 示例用法
string = """
This is line 1.
This is line 2.
This is line 3.
This is line 4.
This is line 5.
"""

pattern = r"This is line \d+."

matched_lines = match_specific_lines(string, pattern)
for line in matched_lines:
    print(line)

This is line 1.
This is line 2.
This is line 3.
This is line 4.
This is line 5.