#!/usr/bin/perl
use warnings;
use strict;

my $filename = 'T7.fa';
open(DNA, $filename);
my @lines = <DNA>;
close DNA;

chomp(@lines);
my $genome = join('',@lines);
print "$genome\n";

##</code><code>##

... # <DNA> opened

my $genome = '';
while (<DNA>) {
    
    chomp($_);
    $genome.=$_;

}

close(<DNA>);
print "$genome\n";