(1) class Structure:
_fields=[]

Def __init__ (self, * args, * * kwargs) :
If len (args) & gt; Len (self. _fields) :
Raise TypeError (' Expected {} the arguments'. The format (len (self. _fields)))
For the name, the value in the zip (self _fields, args) :
Setattr (self, name, value)
For the name in the self. _fields [len (args) :] :
Setattr (self, name, kwargs. Pop (name))
,,,,,,,,
(2) extra_args=kwargs. Keys () - self. _fields
For the name in extra_args:
Setattr (self, name, kwargs. Pop (name))
,,,,,,,,
(3) the class Stock (Structure) :
_fields=[' name ', 'shares',' prices']

S=Stock (ACER, 50, prices=99, the date='2012-2-2')
Print (s.n ame, s.s hares, supachai panitchpakdi rices, spyware doctor ate)


Why does it feel (1) the if len (args) & gt; Len (self _fields) refers to the actual key can't more than the field, then don't and (2) the code inside contradiction?
(3) _fields=[' name ', 'shares',' prices'], only three, but the actual s inside still have one more date dimension, I am not a computer professional, I was just learning, if ask more silly also please forgive me

CodePudding user response:

Kwargs, args is location parameter, is the key word parameters, this want to distinguish
S=Stock (ACER, 50, prices=99, the date='2012-2-2')
This sentence execution, 'ACER and 50 are location parameter, to the args, while prices=99 and date=' 2012-2-2 'to kwargs, the rest is well understood