code: def append(self, term, type=None, value=None):
          
          term = self._normalize(term)
          type = self._normalize(type)
          self.setdefault(term, (odict(), odict()))[0].push((type, True))
          self.setdefault(type, (odict(), odict()))[1].push((term, True))
          self._values[term] = value
docs: Appends the given term to the taxonomy and tags it as the given type.
              Optionally, a disambiguation value can be supplied.
              For example: taxonomy.append("many", "quantity", "50-200")