如何比较一个文件的两行，并报告不匹配的字符？

def compare_lines(line1, line2):
    # 比较两行的长度，取较短的一行作为循环条件
    length = min(len(line1), len(line2))
    mismatched_chars = []

    # 遍历两行的字符进行比较
    for i in range(length):
        if line1[i] != line2[i]:
            mismatched_chars.append((i, line1[i], line2[i]))

    # 如果两行长度不同，将剩余的字符添加到不匹配列表中
    if len(line1) > length:
        for i in range(length, len(line1)):
            mismatched_chars.append((i, line1[i], None))
    elif len(line2) > length:
        for i in range(length, len(line2)):
            mismatched_chars.append((i, None, line2[i]))

    return mismatched_chars

# 示例用法
line1 = "Hello, world!"
line2 = "Hello, there!"
result = compare_lines(line1, line2)

# 输出不匹配的字符及其位置
for index, char1, char2 in result:
    if char1 is None:
        print(f"Character at position {index} in line 1 is missing.")
    elif char2 is None:
        print(f"Character at position {index} in line 2 is missing.")
    else:
        print(f"Character at position {index} does not match: {char1} vs {char2}.")