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Algorithms & data structures easy

Insert an Element Every n Positions in Python

Insert a given element before or after every n-th position in a Python list, returning a new list with the placements applied.

list-manipulation insertion algorithms
Python 
def insert_every_n(seq, element, n, position="after"):
    """Insert an element before or after every n-th position in a list.

    Args:
        seq: Input list
        element: Element to insert
        n: Insert every n positions (n > 0)
        position: 'before' or 'after' (default: 'after')
    Returns:
        …
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