@property
    def _setter(self):
        def set_attr_value(obj, value):
            if value is None or value == self._default:
                if self._clark_name in obj.attrib:
                    del obj.attrib[self._clark_name]
                return
            str_value = self._simple_type.to_xml(value)
            obj.set(self._clark_name, str_value)
        return set_attr_value
Return a function object suitable for the "set" side of the attribute
dataset/ETHPy150Open python-openxml/python-docx/docx/oxml/xmlchemy.py/OptionalAttribute._setter