def add_whitespace(bounding_box: list, border: int = 5) -> list:
    """
    Add white space to an existing bounding box.

    Parameters
    ----------
    bounding_box : list
        Four corner coordinates of the cropped image without whitespace.
    border : int
        The amount of whitespace you want to add on all sides.

    Returns
    -------
    Bounding box with increased whitespace.
    """
    assert len(bounding_box) == 4, "Bounding box can only have 4 corners"

    larger_box = []
    for i, corner in enumerate(bounding_box):
        if i < 2:
            larger_box.append(corner - border)
        else:
            larger_box.append(corner + border)

    return larger_box