code: def add_connective(self, connective):
          
          word_node_id = self.get_element_id(connective)
          # add a key 'connective' to the token with add rel1/rel2 attributes as a dict and
          # add the token to the namespace:connective layer
          connective_attribs = {key: val for (key, val) in connective.attrib.items() if key != 'konn'}
          word_node = self.node[word_node_id]
          word_node['layers'].add(self.ns+':connective')
          word_node.update({'connective': connective_attribs})
docs: Parameters
          ----------
          connective : etree.Element
              etree representation of a <connective> element
              (annotates connective tokens)
  
          Example
          -------
            <word xml:id="s29_1" form="Als" pos="KOUS" lemma="als" func="-"
                  parent="s29_500" dephead="s29_14" deprel="KONJ">
                <connective konn="als" rel1="Temporal" rel2="enable"/>
            </word>