Spotify-downloader: [Feature request] Skip existing songs

[strongboy54]

Hi there,
I was wondering if it were possible to add a feature to skip downloading(Or overwrite) songs that already exist in the folder.
Say I'm downloading 100 different playlists, there are some duplicate songs that will appear.
As everything gets downloaded to the same folder, having a dupe check might be a decent idea to save time.

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[MikhailZex]

We automatically skip existing songs already. What we don't do is skip different versions of the same song.