def register_element_cls(tag, cls):
 (nspfx, tagroot) = tag.split(':')
 namespace = element_class_lookup.get_namespace(nsmap[nspfx])
 namespace[tagroot] = cls

def register_element_cls ( tag , cls ) : ( nspfx , tagroot ) = tag . split ( ':' ) namespace = element_class_lookup . get_namespace ( nsmap [ nspfx ] ) namespace [ tagroot ] = cls
register *cls* to be constructed when the oxml parser encounters an element with matching *tag* .