code: func PlpgsqlCallHandler(db XODB) (pgtypes.LanguageHandler, error) {
  	var err error
  
  	// sql query
  	const sqlstr = `SELECT pg_catalog.plpgsql_call_handler()`
  
  	// run query
  	var ret pgtypes.LanguageHandler
  	XOLog(sqlstr)
  	err = db.QueryRow(sqlstr).Scan(&ret)
  	if err != nil {
  		return pgtypes.LanguageHandler{}, err
  	}
  
  	return ret, nil
  }
docs: // PlpgsqlCallHandler calls the stored procedure 'pg_catalog.plpgsql_call_handler() language_handler' on db.