Partial Inheritance

Solution:

        package Employee;

        sub name {
          my $self = shift;
          my $old_name = $self->SUPER::name;
          if (@_) {
            my $new_name = shift
            $names{$old_name}-- if defined $old_name
            $names{$new_name}++;
            $self->SUPER::name($new_name);
          }
          $self->SUPER::name;
        }

->SUPER::name notation is special
It means "Please call the name method in my superclass"
Control passes to Person::name