code: func Int4rangeCanonical(db XODB, v0 pgtypes.Int4range) (pgtypes.Int4range, error) {
  	var err error
  
  	// sql query
  	const sqlstr = `SELECT pg_catalog.int4range_canonical($1)`
  
  	// run query
  	var ret pgtypes.Int4range
  	XOLog(sqlstr, v0)
  	err = db.QueryRow(sqlstr, v0).Scan(&ret)
  	if err != nil {
  		return pgtypes.Int4range{}, err
  	}
  
  	return ret, nil
  }
docs: // Int4rangeCanonical calls the stored procedure 'pg_catalog.int4range_canonical(int4range) int4range' on db.