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Python Python Collections (2016, retired 2019) Dictionaries Packing and Unpacking Dictionaries

Posted by aa114
aa114
1,697 Points

Why use '=None'?

Why kenneth assinged first and last name to None?

def unpacker(first_name=None, last_name=None):
    if first_name and last_name:
        print("Hi {} {}".format(first_name, last_name))

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

Good question! By specifying default values for the parameters, this allows the function to be called without specifying all of the parameters. If a parameter in your code above is not specified, it will be assigned None. Note that the print statement can only be reached if both parameters have been specified as not None.

>>> unpacker("FName", "LName")
Hi FName LName
>>> unpacker("FName")
>>> unpacker("FName", last_name=None)
>>>

Post back if you have more questions. Good luck!