以一个＊开始的参数，代表一个任意长的元组：
>>> def mul(*arg):... print arg... >>> mul(1,2,3,4,5,6,7,'hello','panfei')(1, 2, 3, 4, 5, 6, 7, 'hello', 'panfei') ＃一个元组>>>
＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊
一个以＊＊开始的参数，代表一个字典：
>>> def mul2(**arg):... print arg... >>> mul2(a=11,b=444,c=888){'a': 11, 'c': 888, 'b': 444} 一个字典>>>
＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊
两种参数前者可以直接写实参，后者写成名＝值的形式！
