code: func AuthUserGroupByUserIDGroupID(db XODB, userID int, groupID int) (*AuthUserGroup, error) {
  	var err error
  
  	// sql query
  	const sqlstr = `SELECT ` +
  		`id, user_id, group_id ` +
  		`FROM auth_user_groups ` +
  		`WHERE user_id = ? AND group_id = ?`
  
  	// run query
  	XOLog(sqlstr, userID, groupID)
  	aug := AuthUserGroup{
  		_exists: true,
  	}
  
  	err = db.QueryRow(sqlstr, userID, groupID).Scan(&aug.ID, &aug.UserID, &aug.GroupID)
  	if err != nil {
  		return nil, err
  	}
  
  	return &aug, nil
  }
docs: // AuthUserGroupByUserIDGroupID retrieves a row from 'auth_user_groups' as a AuthUserGroup.
  //
  // Generated from index 'auth_user_groups_user_id_94350c0c_uniq'.