求平均值代碼如下：
def?average(*args):
????sum?=?0.0
????if?def?average(*args):
????sum?=?0.0
????if?len(args)?==?0:
????????return?sum
????for?x?in?args:
????????sum?=?sum?+?x
????return?sum?/?len(args)
print?average()
print?average(1,?2)
print?average(1,?2,?2,?3,?4)?==?0:
????????return?sum
????for?x?in?args:
????????sum?=?sum?+?x
????return?sum?/?len(args)
print?average()
print?average(1,?2)
print?average(1,?2,?2,?3,?4)

#請問? “len（args）”是什么意思？為什么是這個？