Python method/function arguments starting with asterisk and dual asterisk [duplicate]

Question

I am not able understand where does these type of functions are used and how differently these arguments work from the normal arguments. I have encountered them many time but never got chance to understand them properly.

Ex:

def method(self, *links, **locks):     #some foo     #some bar     return 

I know i could have search the documentation but i have no idea what to search for.

Answer 1

The *args and **keywordargs forms are used for passing lists of arguments and dictionaries of arguments, respectively. So if I had a function like this:

def printlist(*args):     for x in args:         print(x) 

I could call it like this:

printlist(1, 2, 3, 4, 5)  # or as many more arguments as I'd like 

For this

def printdict(**kwargs):     print(repr(kwargs))  printdict(john=10, jill=12, david=15) 

*args behaves like a list, and **keywordargs behaves like a dictionary, but you don't have to explicitly pass a list or a dict to the function.

See this for more examples.