'Returns box from box_id number.'

def get_box(self, box_id):

    box_ids_to_path = self._compute_box_ids()
    loc_in_dashboard = self['layout']
    if (box_id not in box_ids_to_path.keys()):
        raise exceptions.PlotlyError(ID_NOT_VALID_MESSAGE)
    for first_second in box_ids_to_path[box_id]:
        loc_in_dashboard = loc_in_dashboard[first_second]
    return loc_in_dashboard
