<s>[INST] def insert_row_at_interval(rows, interval, new_rows, position):
    """
    Inserts new rows at a specified interval in a list of rows.

    Args:
    rows (list): The original list of rows.
    interval (int): The interval at which to insert new rows.
    new_rows (list): The new rows to be inserted.
    position (str): Either 'before' or 'after', specifying where to insert the new rows.

    Returns:
    list: The updated list of rows.
    """
    if not rows:
        if not new_rows:
            return []
        elif position == 'before':
            return new_rows
        else:
            return new_rows

    updated_rows = []
    for i, row in enumerate(rows):
        updated_rows.append(row)
        if i % interval == 0:
            updated_rows.extend(new_rows if position == 'before' else new_rows[::-1])[/INST]