Python中函数参数传递方法*args, **kwargs，还有其他

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 def the_func(greeting, thing):   print(greeting + ' ' + thing)
 the_func('hello', thing='world')

 the_func('hello', 'world')                  # -> 'hello world' the_func('world', 'hello')                  # -> 'world hello' the_func(greeting='hello', thing='world')   # -> 'hello world' the_func(thing='world', greeting='hello')   # -> 'hello world' the_func('hello', thing='world')            # -> 'hello world'

 def multiply(a, b, *args):   result = a * b   for arg in args:     result = result * arg   return result

 multiply(1, 2)          # returns 2 multiply(1, 2, 3, 4)    # returns 24

 def introduce(firstname, lastname, **kwargs):   introduction = f"I am {firstname} {lastname}"   for key, value in kwargs.items():     introduction += f" my {key} is {value} "   return introduction

 print(introduce(firstname='mike', lastname='huls')) # returns "I am mike huls"
 print(introduce(firstname='mike', lastname='huls', age=33, website='mikehuls.com')) # I am mike huls my age is 33 my website is overfit.cn

 def transfer_money(*, from_account:str, to_account:str, amount:int):   print(f'Transfering ${amount} FORM {from_account} to {to_account}')
 transfer_money(from_account='1234', to_account='6578', amount=9999) # won't work: TypeError: transfer_money() takes 0 positional arguments but 1 positional argument (and 2 keyword-only arguments) were given transfer_money('1234', to_account='6578', amount=9999) # won't work: TypeError: transfer_money() takes 0 positional arguments but 3 were given transfer_money('1234', '6578', 9999)

 def the_func(arg1:str, arg2:str, /):   print(f'provided {arg1=}, {arg2=}')
 # These work: the_func('num1', 'num2') the_func('num2', 'num1')
 # won't work: TypeError: the_func() got some positional-only arguments passed as keyword arguments: 'arg1, arg2' the_func(arg1='num1', arg2='num2') # won't work: TypeError: the_func() got some positional-only arguments passed as keyword arguments: 'arg2' the_func('num1', arg2='num2')

 def exceeds_100_bytes(x, /) -> bool:   return x.__sizeof__() > 100
 exceeds_100_bytes('a')       exceeds_100_bytes({'a'})

def len(__obj: Sized) -> int:

 def len_new(x, /, *, no_duplicates=False):   if (no_duplicates):     return len(list(set([a for a in x])))   return len(x)

 print(len_new('aabbcc'))                                  # returns 6 print(len_new('aabbcc', no_duplicates=True))              # returns 3 print(len_new([1, 1, 2, 2, 3, 3], no_duplicates=False))   # returns 6 print(len_new([1, 1, 2, 2, 3, 3], no_duplicates=True))    # returns 3
 # Won't work: TypeError: len_() got some positional-only arguments passed as keyword arguments: 'x' print(len_new(x=[1, 1, 2, 2, 3, 3])) # Won't work: TypeError: len_new() takes 1 positional argument but 2 were given print(len_new([1, 1, 2, 2, 3, 3], True))

 def the_func(pos_only1, pos_only2, /, pos_or_kw1, pos_or_kw2, *, kw1, kw2, **extra_kw):   # cannot be passed kwarg   <--   | --> can be passed 2 ways | --> can only be passed by kwarg   print(f"{pos_only1=}, {pos_only2=}, {pos_or_kw1=}, {pos_or_kw2=}, {kw1=}, {kw2=}, {extra_kw=}")

 # works (pos_or_kw1 & pow_or_k2 can be passed positionally and by kwarg) pos_only1='pos1', pos_only2='pos2', pos_or_kw1='pk1', pos_or_kw2='pk2', kw1='kw1', kw2='kw2', extra_kw={} pos_only1='pos1', pos_only2='pos2', pos_or_kw1='pk1', pos_or_kw2='pk2', kw1='kw1', kw2='kw2', extra_kw={} pos_only1='pos1', pos_only2='pos2', pos_or_kw1='pk1', pos_or_kw2='pk2', kw1='kw1', kw2='kw2', extra_kw={'kw_extra1': 'extra_kw1'}
 # doesnt work, (pos1 and pos2 cannot be passed with kwarg) # the_func(pos_only1='pos1', pos_only2='pos2', pos_or_kw1='pk1', pos_or_kw2='pk2', kw1='kw1', kw2='kw2')
 # doesnt work, (kw1 and kw2 cannot be passed positionally) # the_func('pos1', 'pos2', 'pk1', 'pk2', 'kw1', 'kw2')

 def func(x,/,y,*,z,**k):