package Person;
use Moose;

has 'label'      => ( is => 'rw', isa => 'Str' );
has 'shift'      => ( is => 'rw', isa => 'Str' );

#### then, in the script

my $Person = Person->new;

if($hash->{label})     { $Person->label( $hash->{label} );  }
if($hash->{shift})     { $Person->shift( $hash->{shift} );  }