编辑代码

# coding:utf-8
def homework():
    url = "www.moe.gov.cn"
    print(url[0])
    print(url[0:3])
    print(url[-3:])
    print(len(url))
    print(url.index('o'))
    print(url.count('o'))
    print(url.replace('.', "-"))
    print(url.upper())
    print(url.split("."))
    print(url)
    # 上面的操作都是对 url 没有影响
    # 只有 url 被赋值改变的时候才会被改变

def __main():
    homework()

__main()