Using a function with multiple parameters with `map`

Question

I\'m trying to map a function that takes 2 arguments to a list:

my_func = lambda index, value: value.upper() if index % 2 else value.lower()

import string
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Answer 1

Python cannot unpack lambda parameters automatically. enumerate returns a tuple, so lambda has to take that tuple as sole argument

You need:

n = map(lambda t: t[1].upper() if t[0] % 2 else t[1], enumerate(alphabet))

Considering now the ugliness of map + lambda + manual unpacking, I'd advise the alternate generator comprehension instead:

n = (value.upper() if index % 2 else value for index,value in enumerate(alphabet))

(I removed the lower() call since your input is already lowercase)