generally you can do something like this:

use Module::Load;
sub get_object
{
    my ($class, $href) = @_;
    load $class;
    return bless $href, $class;
}
[download]

but, it will not work for any package. Also instead of bless you can call a constructor:

    return $class->new($href);
[download]

but again, it won't work for any package.