如何提取字符串中整数值的第二个实例

def extract_second_integer(string):
    count = 0
    temp = ""
    for char in string:
        if char.isdigit():
            temp += char
        elif temp != "":
            count += 1
            if count == 2:
                return int(temp)
            temp = ""
    return None  # 如果字符串中没有第二个整数，则返回None或其他适当的值

# 示例用法
string = "abc123def456ghi789"
second_integer = extract_second_integer(string)
print(second_integer)  # 输出：456