This one is just unbearable. can't you just do one of the two below:  ``` value['option_ids'].union(option_line_ids.ids) ```  or, within the for loop just above  ``` value['option_ids'].add(option_line_id.id) ```  Your code must always be the most readable possible for a newbie. Always think that someone will have to read your code after you wrote it. 