python reduce()函数    python reduce 函数    python的reduce函数    python mean()函数    python中的reduce函数    python next()函数    python head()函数    python copy()函数    reduce函数的用法python    python reduce函数用法    python中reduce()函数的作用    python round 函数    python中str()函数    python range 函数    python中reduce函数    python 常用的函数    python 绝对值函数    python sorted函数    python sample函数    python decode函数    python filter函数    python import函数    python中count函数    python中write函数    python中range函数    python中index函数    reduce函数python    python assert()函数    reverse函数python    python中join函数怎么用    python的f函数用法    python的groupby中函数详解    python的super()函数功能    get函数python用法    python中range()函数    python的isinstance函数    python中的join()函数的用法    python join()函数的功能和用法    python rstrip函数的用法    python for in 函数    python unstack()函数    python isalpha()函数    python isdigit()函数    python quantile函数    strftime函数 python    python isinstance函数    python with open函数用法    python strip()函数    python中的reverse函数    python中的super函数