or download this
package My::New::Object;
...
has fh => (is=>'rw', isa=>'My::New::Object::ProtoFileHandle', clearer=
+>'clear_fh', predicate=>'has_fh', writer=>'_set_fh', coerce => 1, ini
+t_arg => 'file', trigger => \&reset_temporary_variables );
[... more attributes, code, etc. ]