def _update_trait(self, event):

        self._set_trait(notify=False)

        self.obj.trait_property_changed(
            self.trait_name + '_items', Undefined, event
        )

        return
test with valid fully qualified domain name url
dataset/ETHPy150Open enthought/envisage/envisage/extension_point_binding.py/ExtensionPointBinding._update_trait--crossover with--dataset/ETHPy150Open alecthomas/voluptuous/voluptuous/tests/tests.py/test_fqdn_url_validation