open IN, '<:encoding(UTF-8)', "WE_EX.txt"
open OUT, '>:encoding(UTF-8)', "WE_EX.out"

##</code><code>##

while (<IN>) {

##</code><code>##

use strict;
use warnings;

open(my $IN, '<:encoding(UTF-8)', 'WE_EX.txt')
    or die "Can't open file WE_EX.txt for reading: $!";

open(my $OUT, '>:encoding(UTF-8)', 'WE_EX.out')
    or die "Can't open file WE_EX.out for writing: $!";

while (<$IN>) {
    # ... Manipulate $_ ...
    print $OUT $_;
}

close $IN;
close $OUT;