List comprehensions
List comprehensions are expressions that allow us to transform lists in a single line. The syntax:

[ <inner_expression> for <item> in <list> ]

It may look intimidating at first glance but what will happen is python loops through the list and executes the <inner_expression> for each <item> in <list> to create a new list.

# Example
nums = [1, 2, 3, 4, 5]
squared = [n ** 2 for n in nums]
print(squared)

# output: [1, 4, 9, 16, 25]

Above we have two expression the outer_expression which is the list comprehension itself and the inner_expression (n ** 2) which transforms the list. In this case the inner_expression squares each item from the list.

#PythonTips #GettingToKnowPython #PythonPatterns