You haven't assigned anything to %seen.

Maybe add

    $seen{$file} = $version;
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before the print statement.   Or even

    push @{ $seen{$file} }, $version;
    print "@{$seen{$file}} \n";
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as the $file part (hash key) seems to be the same in all cases (at least for the sample data).  The latter would create an array for a hash entry/key "/view/d602_edf3/" with the array holding all values of $version...

Maybe you could elaborate on what exactly you're trying to achieve.