Duplicates of files on Debian Linux

I can find a duplicate or duplicates of files using:

fdupes -r /left /right  

where files in the left and right directories are compared with using MD5SUM. The tool will find files recursively, that is, looking for files in the other directories in the left and right directories.

I can also use:

fdupes -rd /left /right

where a duplicate or duplicates will be deleted. Only one copy will be preserved.

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