Using **kwargs in alternating letter exercise

Question

Hello I was wondering why using **kwargs is not working in this example. I was following the answer as given in Alternating letter in python

def myfunc(**kwargs):
    return "".join(w.upper() if i%2 else w.lower() for i,w in enumerate(kwargs))

I have tried calling the function as myfunc("skyscraper") but get the error:

TypeError: myfunc() takes 0 positional arguments but 1 was given

Its probably something simple but not obvious to me. In the exercise says I am not allowed to use print statements and the function as to return a string Thanks

`**argumentname` gives your function all unmatched arguments that were passed by keyword as a dictionary. — Steven Rumbalski, Jun 07 '19 at 16:59
Possible duplicate of [What does \*\* (double star/asterisk) and \* (star/asterisk) do for parameters?](https://stackoverflow.com/questions/36901/what-does-double-star-asterisk-and-star-asterisk-do-for-parameters) — manveti, Jun 07 '19 at 17:00
you need to define a argument and use the name fo the argument to access the value. see my answer @yong_m — Devesh Kumar Singh, Jun 07 '19 at 17:21

score 0 · Answer 1 · answered Jun 07 '19 at 17:01

0

**kwargs deals with keyword arguments. try using:

myfunc(somekeyword="skyscraper")

answered Jun 07 '19 at 17:01

paul

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2
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Hi Paul, I am not sure though how could I change the function I've define to include this keyword I have tried defining inisde the function ``` python result = "".join(w.upper() if i%2 else w.lower() for i,w in enumerate(kwargs))``` and return result but that has not work. – yong_m Jun 07 '19 at 17:13
@yong_m: you need to change the call, not the function itself – paul Jun 07 '19 at 17:24

score 0 · Accepted Answer · answered Jun 07 '19 at 17:17

You would need to pass a keyword argument to the function e.g. myfunc(arg="skyscraper"), and then use the name of the keyword argument in the function to extract out the value.

For example

def myfunc(**kwargs):
    #arg is the name of the argument, you extract the value from the kwargs dictionary
    return "".join(w.upper() if i%2 else w.lower() for i,w in enumerate(kwargs['arg']))

#Call myfunc using kwargs
print(myfunc(arg="skyscraper"))

The output will be

sKyScRaPeR

Using **kwargs in alternating letter exercise

2 Answers2