Python Mastery: 101 Pythonic Ways to Use List Comprehensions

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List comprehensions are a concise and expressive way to create lists in Python. They provide a compact syntax for generating lists by applying an expression to each item in an iterable (such as a list, tuple, or range) and optionally filtering the items based on a condition. List comprehensions are a fundamental feature of Python and are considered Pythonic due to their readability and efficiency.

The basic syntax of a list comprehension is as follows:

[expression for item in iterable if condition]

• expression: The expression to evaluate and include in the new list.
• item: The variable representing each element in the iterable.
• iterable: The source of elements to iterate over.
• condition (optional): A filter that determines whether to include the item in the new list.

1. Create a list of squares:

squares = [x**2 for x in range(10)]
# Result: [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]

2. Filter even numbers:

evens = [x for x in range(10) if x % 2 == 0]
# Result: [0, 2, 4, 6, 8]

3. Flatten a 2D list:

matrix = [[1, 2, 3], [4, 5…