如何从.txt文件中搜索一行文本？

def search_text_in_file(file_path, target_text):
    line_number = 0
    matching_lines = []

    with open(file_path, 'r') as file:
        for line in file:
            line_number += 1
            if target_text in line:
                matching_lines.append((line_number, line))

    return matching_lines

file_path = 'example.txt'
target_text = 'search this line'

result = search_text_in_file(file_path, target_text)

if result:
    print("Matching lines found:")
    for line_number, line in result:
        print(f"Line {line_number}: {line}")
else:
    print("No matching lines found.")