code: def list_entity_types(namespace, workspace):
      
      headers = _fiss_agent_header({"Content-type":  "application/json"})
      uri = "workspaces/{0}/{1}/entities".format(namespace, workspace)
      return __get(uri, headers=headers)
docs: List the entity types present in a workspace.
  
      Args:
          namespace (str): project to which workspace belongs
          workspace (str): Workspace name
  
      Swagger:
          https://api.firecloud.org/#!/Entities/getEntityTypes