package Person;
use strict;
use warnings;

sub new {
    my $class = shift;
    my $self = {
        _firstName => shift,
        _lastName  => shift,
        _ssn       => shift,
    };
    # Print all the values just for clarification.
    print "First Name is $self->{_firstName}\n";
    print "Last Name is $self->{_lastName}\n";
    print "SSN is $self->{_ssn}\n";
    bless $self, $class;
    return $self;
}
sub setFirstName {
    my ( $self, $firstName ) = @_;
    $self->{_firstName} = $firstName if defined($firstName);
    return $self->{_firstName};
}
sub getFirstName {
    my( $self ) = @_;
    return $self->{_firstName};
}



package Employee;
use strict;
use warnings;
our @ISA = qw(Person);    # inherits from Person



package main;
use strict;
use warnings;
use Data::Dumper;

my $object = Person->new( "Thanos", "Test", 123456);
print Dumper $object;

$object = Employee->new( "Janus", "Employee", 998877);
print Dumper $object;
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