use SL::DB::MetaSetup::RequirementSpecItem;
use SL::DB::Manager::RequirementSpecItem;
use SL::DB::Helper::ActsAsList;
+use SL::DB::Helper::AttrDuration;
__PACKAGE__->meta->add_relationship(
children => {
__PACKAGE__->meta->initialize;
__PACKAGE__->configure_acts_as_list(group_by => [qw(requirement_spec_id parent_id)]);
+__PACKAGE__->attr_duration(qw(time_estimation));
__PACKAGE__->before_delete(\&_before_delete_delete_children);