For macOS 10.10 and later. This script will look for an image file in the parent folder of each selected track's file--presumably its Album folder in which you have previously placed an image file of some sort--and apply the data from that image file as artwork for the track.
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Remove iTunes tracks disassociated from files
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Droplet adds files, creates playlists based on folder name(s)
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Recreate a playlist such that its visible columns mirror the Music library