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Lists & loops

Iterate, transform, and combine sequences with readable loop patterns.

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Lists & loops easy

How to Truncate a List to Max Length in Python (Keep Head)

This code returns a new list containing only the first max_length items from the original list, using Python's slice syntax.

list slicing truncate
Python 
from typing import List

def truncate_head(lst: List[object], max_length: int) -> List[object]:
    """Return a new list with at most max_length items from the head."""
    if max_length < 0:
        raise ValueError("max_length must be non-negative")
    return lst[:max_length]

if __name__ == "__main__":
    # Examp…
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