docs: def es_get_class_defs(cls_def, cls_name):
      """
      Reads through the class defs and gets the related es class
      defintions
  
      Args:
      -----
          class_defs: RdfDataset of class definitions
      """
      rtn_dict = {key: value for key, value in cls_def.items() \
                  if key.startswith("kds_es")}
      for key in rtn_dict:
          del cls_def[key]
      return rtn_dict