Reference library

Comprehensions & generators

List/dict/set comprehensions, generator expressions, and lazy iteration.

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Comprehensions & generators easy

Count Data in Python with Comprehensions and Generators

Count list items with a dict comprehension and generate squares lazily with a generator expression, printing both results.

comprehensions generators counter
Python 
from collections import Counter

data = ["apple", "banana", "apple", "cherry", "banana", "apple"]

counts = {item: data.count(item) for item in set(data)}

square_gen = (x * x for x in range(5))
squares = list(square_gen)

if __name__ == "__main__":
    print("Manual count:", counts)
    print("Counter:", dict(Counter…
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Comprehensions & generators — Python code examples

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