code: def set_parent_on_new(self, parentrefobj):
          
          refobjinter = self.get_refobjinter()
          # to make sure we only get the new one
          # we get all current unwrapped first
          old = self.get_unwrapped(self.get_root(), refobjinter)
          yield
          new = self.get_unwrapped(self.get_root(), refobjinter) - old
          for refobj in new:
              if refobjinter.get_parent(refobj) is None:
                  refobjinter.set_parent(refobj, parentrefobj)
docs: Contextmanager that on close will get all new
          unwrapped refobjects, and for every refobject with no parent
          sets is to the given one.
  
          :returns: None
          :rtype: None
          :raises: None