code: AtlasVertex findVertex(DataTypes.TypeCategory category, String typeName) {
          LOG.debug("Finding AtlasVertex for {}.{}", category, typeName);
  
          Iterator results = graph.query().has(Constants.TYPENAME_PROPERTY_KEY, typeName).vertices().iterator();
          AtlasVertex vertex = null;
          if (results != null && results.hasNext()) {
              //There should be just one AtlasVertex with the given typeName
              vertex = (AtlasVertex) results.next();
          }
          return vertex;
      }
docs: Find vertex for the given type category and name, else create new vertex
  @param category
  @param typeName
  @return vertex