use List::MoreUtils qw( uniq );

sub Remove_duplicate_lines {

  my ($processed_file, $out_file) = @_;

  open (PROCESSED_FILE, "<$processed_file");
  chomp( my @array = <PROCESSED_FILE> );
  close PROCESSED_FILE;

  my @unique = uniq @array;

  open (OUTFILE, "+>$out_file");
  print OUTFILE join( '', @array );
  close OUTFILE;
}
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