use Bio::LocatableSeq ();
use Bio::SimpleAlign  ();
    
my $aln = Bio::SimpleAlign->new();

foreach (qw/ AAAAAAAAAAAAAAA AAAAAAAGGAAACCA /) {
   $aln->add_seq(
      Bio::LocatableSeq->new(
         '-seq'   => $_,
         '-start' => 1,
         '-end'   => length($_),
      )
   );
}

print("IDENTITY : ", $aln->percentage_identity, "\n");
print("CONSENSUS: ", $aln->consensus_string(28), "\n");