Reference library

Comprehensions & generators

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

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Comprehensions & generators easy

How to Implement takewhile Generator in Python

A generator that yields items from an iterable until a condition fails, like itertools.takewhile.

generator takewhile iteration
Python 
def takewhile(predicate, iterable):
    for item in iterable:
        if not predicate(item):
            break
        yield item

if __name__ == "__main__":
    numbers = [1, 2, 3, 4, 5, 1, 2, 3]
    result = list(takewhile(lambda x: x < 4, numbers))
    print(result)
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Comprehensions & generators — Python code examples

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