Return True if workflow is fully completed.

def has_completed(self):
        """Return True if workflow is fully completed."""
        objects_in_db = WorkflowObjectModel.query.filter(
            WorkflowObjectModel.id_workflow == self.uuid,
            WorkflowObjectModel.id_parent == None,  # noqa
        ).filter(WorkflowObjectModel.status.in_([
            workflow_object_class.known_statuses.COMPLETED
        ])).count()
        return objects_in_db == len(list(self.objects))