code: def delete_session_entity_type(project_id, session_id,
                                 entity_type_display_name):
      
      import dialogflow_v2 as dialogflow
      session_entity_types_client = dialogflow.SessionEntityTypesClient()
  
      session_entity_type_name = (
          session_entity_types_client.session_entity_type_path(
              project_id, session_id, entity_type_display_name))
  
      session_entity_types_client.delete_session_entity_type(
          session_entity_type_name)
docs: Delete session entity type with the given entity type display name.