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

open my $hairpin_file, '<', "test.hairpin", or die $!;

my %HoA_sequences;

while (my $line = <$hairpin_file>){
	if ($line =~ /^>hsa/){
		$HoA_sequences{$line} = 
## Do I provide the key for the hash as soon as I read in the line bearing the sequence name?
## And can I create a hash with a key but no hash? I'm guessing not. :/
	}

}