Notes:

• I wasn't able to test this script on MacOS. I tested it on Windows and Linux and it worked fine,
• The How-To-Guide might seem to over-explain everything, but I wanted people who aren't experienced with programming and such things to be able to use this script as well

How To Use

1. download the repository,
2. install python3 (Python download page)
3. locate all the folders you want to search for duplicate files and copy their absolute path into searchSpace.txt (use a new line for each path),
4. for each file extension of which you want to find duplicates: write the file extension into fileTypes.txt (again, use a new line for each type). E.g. when you want to find duplicate PNGs write a line with .png
5. go inside the folder of dff.py and run python3 dff.py -f searchSpace.txt -t fileTypes.txt [-r] (-r being in square brackets means that this is optional. If set the subdirectories of the folders in searchSpace.txt will be searched recursively for duplicates as well. If you don't want this, leave it out of the command.) Note: you don't have to use the available files searchSpace.txt and fileTypes.txt. You can make your own files (located where ever you want) and provide their paths as arguments.
6. after the code finished you will find all the duplicates in the corresponding folder in the duplicates folder. Also there will be a .txt file where you can see for each duplicate, where it was found. Only the first found occurance of a file will stay in its original place. Every duplicate of that will be moved to the duplicates folder.