code: func (au *AuthUser) Insert(db XODB) error {
  	var err error
  
  	// if already exist, bail
  	if au._exists {
  		return errors.New("insert failed: already exists")
  	}
  
  	// sql insert query, primary key provided by sequence
  	const sqlstr = `INSERT INTO public.auth_user (` +
  		`password, last_login, is_superuser, username, first_name, last_name, email, is_staff, is_active, date_joined` +
  		`) VALUES (` +
  		`$1, $2, $3, $4, $5, $6, $7, $8, $9, $10` +
  		`) RETURNING id`
  
  	// run query
  	XOLog(sqlstr, au.Password, au.LastLogin, au.IsSuperuser, au.Username, au.FirstName, au.LastName, au.Email, au.IsStaff, au.IsActive, au.DateJoined)
  	err = db.QueryRow(sqlstr, au.Password, au.LastLogin, au.IsSuperuser, au.Username, au.FirstName, au.LastName, au.Email, au.IsStaff, au.IsActive, au.DateJoined).Scan(&au.ID)
  	if err != nil {
  		return err
  	}
  
  	// set existence
  	au._exists = true
  
  	return nil
  }
docs: // Insert inserts the AuthUser to the database.