Ensures valid view/dimensions are selected.

def check_views(view_set, max_views=3):
    """Ensures valid view/dimensions are selected."""

    if not isinstance(view_set, Iterable):
        view_set = tuple([view_set, ])

    if len(view_set) > max_views:
        raise ValueError('Can only have {} views'.format(max_views))

    return [check_int(view, 'view', min_value=0, max_value=max_views - 1) for view in view_set]