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Pluck values from list of dictionaries | Challenge

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Introduction

In Python, a dictionary is a collection of key-value pairs. Sometimes, we need to extract specific values from a list of dictionaries. In this challenge, you need to write a function that takes a list of dictionaries and a key as input and returns a list of values corresponding to the specified key.

Skills Graph

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Pluck values from list of dictionaries

Problem

Write a function pluck(lst, key) that takes a list of dictionaries lst and a key key as arguments and returns a list of values corresponding to the specified key.

You need to:

  • Use a list comprehension and dict.get() to get the value of key for each dictionary in lst.
  • The function should return an empty list if the input list is empty or if the specified key is not present in any of the dictionaries.

Example

simpsons = [
  { 'name': 'lisa', 'age': 8 },
  { 'name': 'homer', 'age': 36 },
  { 'name': 'marge', 'age': 34 },
  { 'name': 'bart', 'age': 10 }
]
print(pluck(simpsons, 'age')) ## [8, 36, 34, 10]

Summary

In this challenge, you learned how to extract specific values from a list of dictionaries using a list comprehension and dict.get(). You also learned how to handle empty input lists and non-existent keys.

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