code: public static GrammaticalRelation getConj(String conjunctionString) {
      GrammaticalRelation result = conjs.get(conjunctionString);
      if (result == null) {
        synchronized(conjs) {
          result = conjs.get(conjunctionString);
          if (result == null) {
            result = new GrammaticalRelation(Language.English, "conj", "conj_collapsed", null, CONJUNCT, conjunctionString);
            conjs.put(conjunctionString, result);
            threadSafeAddRelation(result);
          }
        }
      }
      return result;
    }
docs: The "conj" grammatical relation. Used to collapse conjunct relations.
  They will be turned into conj_word, where "word" is a conjunction.
  
  NOTE: Because these relations lack associated GrammaticalRelationAnnotations,
  they cannot be arcs of a TreeGraphNode.
  
  @param conjunctionString The conjunction to make a GrammaticalRelation out of
  @return A grammatical relation for this conjunction