perl api printing variables
===

The common code is :

    use strict;
    use warnings;

    my $f = $ARGV[0];
    use Bio::EnsEMBL::Registry;
    use Bio::EnsEMBL::ApiVersion;

    my $registry = 'Bio::EnsEMBL::Registry';
    $registry->load_registry_from_db(
    -host => 'ensembldb.ensembl.org',
    -user => 'anonymous',
    -port => '5306'
    );

    my $adaptor = $registry->get_adaptor( 'Homo sapiens', 'core', 'transcript' );

    my $transcript =
    $adaptor->fetch_by_translation_stable_id($f);


LAST LINE 
#########################################

For the LAST LINE, I am having trouble printing out the two values as two columns in the same line :

Attempt 1 code: print $f . $transcript->display_id. "\n";

Result : api.test.pl ENSP00000418690 
 
ENSP00000418690ENST00000488594

Attempt 2 code :print $f, $transcript->display_id. "\n";

Result : perl api.test.pl ENSP00000418690 :
 
ENSP00000418690ENST00000488594


Any other attempt messes with accessing the display_id. What I want the format to be is :
ENSP00000418690   ENST00000488594



