1.接受任意长度形参，组成turple

python">def function(*args):# type(args)==turple# args==(1, 2, 3, 4)print(args)ant=0for i in range(len(args)):ant+=args[i]return antprint(function(1,2,3,4))  # 10

 2.接受任意长度形参，组成dict

python">def function(**args):# type(args)==<class'dict'>print(type(args))# {'a': 1, 'b': 2, 'c': 3, 'd': 4}print(args)ants = 0for key in args:ants+=args[key]return antsprint(function(a=1,b=2,c=3,d=4))   # 10# 注意这种方法是错误的
print( function({"a":1,"b":2,"c":3,"d":4}) )
# TypeError: function() takes 0 positional arguments but 1 was given

python">def my_function(**kwargs):# {'a': 1, 'b': 2}print(kwargs)my_dict = {'a': 1, 'b': 2}
my_function(**my_dict)

 3. 拿出参数

在list中 

python">def sample_function(a, b, c):print(a, b, c)list = [1, 2, 3]sample_function(*list)list2=[10,list,20]
list3=[10,*list,20]
# [10, [1, 2, 3], 20]
print(list2)
# [10, 1, 2, 3, 20]
print(list3)

在turple中 

python">def sample_function(a, b, c):print(a, b, c)list = (1, 2, 3)sample_function(*list)list2=(10,list,20)
list3=(10,*list,20)
# (10, (1, 2, 3), 20)
print(list2)
# (10, 1, 2, 3, 20)
print(list3)

4.函数传参对号入座

python">def test(a, b):print(f"a={a}, b={b}")d = {'b': 200, 'a':30}
test(**d)

参数和形参名称不对应，报错 

python">def test(c,d):print(c," ",d)
d = {'b': 100, 'a':10}
test(**d)
"""
File "d:\WorkSpace\MachineLearning\d2l_learn\mainTest2.py", line 4, in <module>test(**d)
TypeError: test() got an unexpected keyword argument 'b'
"""

题外话：看到*args和**kwds既不害怕了

python">class Person(object):def __init__(self) -> None:passdef __call__(self, *args: Any, **kwds: Any) -> Any:passdef __new__(cls) :pass