Python function parameters

1. Position parameter/position parameter
2. Default parameters
   The default parameter must point to an immutable object, especially when an empty list is used as a function parameter.
   

   def f (L = None)    Pass

   Instead of

   def f (L = [])    Pass

3. Variable parameters
   The variable parameter *args can be passed in any parameter, including 0, and the transfer form is turple
4. Keyword parameter **kw
   The keyword parameter **kw into the key-value as a dictionary, and kw obtains the copy value of the incoming dictionary
5. Named keyword parameters
   On the basis of the keyword argument, limit the key value of the passed-in dictionary element. The form is the argument after the delimiter * is treated as a named keyword argument

Python function parameters