Are you lazy?... or Maybe you are sick of copying and pasting the stages name one by one, or do you want to save time?
Here is my old and favorite tools: the Stage list creator EASY AND QUICK even if you have many stage
Here is the process: Sorry but I don't know how to put a video here so I hope you will understand my instruction

1. Unzip the file ;after you will see the tool "00_StageListCreator " and a text file "01_StageList"
2. Copy them on your stages folder
3. Double Click on the tool and it will automatically list all your characters on the text file
4. Double click the text file and you’ll see all your Stages in alphabetical order
5. You just need to copy them once and paste them into your select.def.
6. Enjoy your Game