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List comprehensions
Lesson 31 of 77
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PYTHON INTERMEDIATEChapter 6 · Comprehensions and data tools

List comprehensions

A list comprehension is a concise way to create lists. It replaces standard loops with a single line: [expression for item in iterable if condition].

Worked example

How it reads

  • **[x * 2 for x in nums]** loops through nums and returns doubled values
  • if x % 2 == 0 filters the input list keeping only evens
Cloud tip: Comprehensions are faster and more readable, but do not make them too complex or nested.
main.py
PYTHON
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Console
Run your code to see its output here.
YOUR TURN

Build squares with a comprehension that holds the square of every number in nums, then print it: [25, 144, 64, 441].

Press Run to check your work.
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