Learn Python in 30 Days — Day 22: Lists & Dictionary Comprehensions
Day 22: Lists & Dictionary Comprehensions Welcome to Day 22 of the Learn Python in 30 Days series! Today we get into one of Python’s cleanest “superpowers”: comprehensions . These let you build lists, dictionaries, and sets in a single, readable line, perfect for filtering data, transforming it, or generating new structures without writing full loops. By the end of today, you’ll know how to: Turn long loops into compact one-liners Build new lists from existing data Filter items based on conditions Create dictionaries on the fly Use comprehensions with nested structures This is the kind of Python feature that instantly makes your code cleaner and easier to read. All example files for this series are available on my GitHub: Learn-Python-in-30-Days What Is a Comprehension? A comprehension is a compact way to create a new list or dictionary by looping over something. squares = [] for n in range ( 1 , 6 ): squares.append(n * n) ...