python中*和**的使用

调用函数时用*

def test1(a,b,c):
    print(a,b,c)

args=(1,2,3)
test1(*args)

输出:

1 2 3

调用函数时用**

def test2(d,e,f):
    print(d,e,f)

kwargs = {'d':4,'e':5,'f':6}
test2(**kwargs)

输出:

4 5 6

定义函数时用*

def test3(*args):
    print(args)

test3(7,8,9)

输出:

(7, 8, 9)

定义函数时用**

def test4(**kwargs):
    print(kwargs)

test4(g=10,h=11,i=12)

输出:

{'g': 10, 'h': 11, 'i': 12}