code: def get_path_to_root(self,termid):
                  
          # Get the sentence for the term
          root = None
          sentence = self.sentence_for_termid.get(termid)
          
          if sentence is None:    #try with the top node
              top_node = self.top_relation_for_term.get(termid)
              if top_node is not None:
                  root = top_node[1]
              else:
                  return None
          else:
              if sentence in self.root_for_sentence:
                  root = self.root_for_sentence[sentence]
              else:
                  ##There is no root for this sentence
                  return None
          # In this point top_node should be properly set
          path = self.get_shortest_path(termid, root)
          return path
docs: Returns the dependency path from the term to the root
          @type termid: string
          @param termid: the term identifier
          @rtype: list
          @return: list of dependency relations