code: def save(self):
          
          props = self.deflate(self.__properties__)
          query = "MATCH ()-[r]->() WHERE id(r)={self} "
          for key in props:
              query += " SET r.{0} = {{{1}}}".format(key, key)
          props['self'] = self.id
  
          db.cypher_query(query, props)
  
          return self
docs: Save the relationship
  
          :return: self