Add a ``_new_{prop_name}()`` method to the element class that creates
        a new, empty element of the correct type, having no attributes.

def _add_creator(self):
        """
        Add a ``_new_{prop_name}()`` method to the element class that creates
        a new, empty element of the correct type, having no attributes.
        """
        creator = self._creator
        creator.__doc__ = (
            'Return a "loose", newly created ``<%s>`` element having no attri'
            'butes, text, or children.' % self._nsptagname
        )
        self._add_to_class(self._new_method_name, creator)