Map list to dictionary

OSCC · Python, List, Dictionary · Nov 2, 2020

Maps the values of a list to a dictionary using a function, where the key-value pairs consist of the original value as the key and the result of the function as the value.

• Use map() to apply fn to each value of the list.
• Use zip() to pair original values to the values produced by fn.
• Use dict() to return an appropriate dictionary.

def map_dictionary(itr, fn):
  return dict(zip(itr, map(fn, itr)))

map_dictionary([1, 2, 3], lambda x: x * x) # { 1: 1, 2: 4, 3: 9 }

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