List comprehensions are a way to create lists in a very concise way.
Suppose you have a list:
numbers = [1, 2, 3, 4, 5]
You can create a new list using a list comprehension, composed by the
numbers list elements, power 2:
numbers_power_2 = [n**2 for n in numbers] # [1, 4, 9, 16, 25]
List comprehensions are a syntax that’s sometimes preferred over loops, as it’s more readable when the operation can be written on a single line:
numbers_power_2 =  for n in numbers: numbers_power_2.append(n**2)
numbers_power_2 = list(map(lambda n : n**2, numbers))
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