def METHOD_NAME(elem):
    """ Parse one bounding-box input item value. """
    args = {}
    lower_corner = elem.findtext("./"+ns_ows("LowerCorner"))
    upper_corner = elem.findtext("./"+ns_ows("UpperCorner"))
    if lower_corner is None or upper_corner is None:
        raise ValueError("Invalid 'wps:BoundingBoxData' element!")
    args['data'] = (lower_corner, upper_corner, elem.attrib.get("crs"))
    return args