3) Re-writing a FASTA file containing one protein sequence of TERT

It will open original fasta file with TERT protein sequence and print&save on another new file: 

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

 open(FASTA1, "TERTpr.fasta") or die;
 open(FASTA2, ">>TERTpr_rewritten.fasta") or die;

 while (<FASTA1>) {
 print FASTA2 "$_\n";
}