def create_pad(size, pad_id):
    """
    Create a padding list of a given size

    Args:
        size: nd list shape
        pad_id: padding index

    Returns:
        - padding list of the given size
    """
    if len(size) == 1:
        return [pad_id for _ in range(size[0])]
    else:
        return [create_pad(size[1:], pad_id) for _ in range(size[0])]