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Comprehensions & generators

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

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Comprehensions & generators easy

How to Create a Line-Numbered Generator with enumerate start in Python

This Python code defines a generator that yields lines prefixed with their index, using enumerate's start parameter to offset numbering.

enumerate generator yield
Python 
def line_numbered_lines(lines, start=1):
    for idx, line in enumerate(lines, start):
        yield f"{idx:3} {line}"


if __name__ == "__main__":
    sample = ["first line", "second", "third"]
    for numbered in line_numbered_lines(sample, start=10):
        print(numbered)
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