sort() and sorted() accept several optional parameters.

Should default values for those optional parameters be documented? (E.g. I think both for sort and key None is the default value)

Explicitly documented defaults are needed, e.g. if you need to write a wrapper.

 def  sortWrapper( data, userKey=None)
        #do something
        data.sort(key=userKey)

(if you don't know the default values, you have to write something ugly like:

 def  sortWrapper( data, userKey=None)
        #do something
        if userKey is None:
           data.sort()
        else:
           data.sort(userKey) 


Or am I missing something?