docs: private ODocument getModel(String model) {
          String query = String.format("select from Models where %s = ?", OGraphDatabase.LABEL);
          List<ODocument> from = graph.query(new OSQLSynchQuery<ODocument>(query), model);
          if (from.size() > 0) {
              return from.get(0);
          } else {
              return null;
          }
      }