ui.py

    def update(self):

        for cc in self.controller.charm_classes():
            if self.machine:
                if not satisfies(self.machine, cc.constraints)[0] \
                   or not self.controller.is_assigned(cc, self.machine):
                    self.remove_service_widget(cc)
                    continue

            if self.unplaced_only:
                n_units = self.controller.machine_count_for_charm(cc)
                if n_units == cc.required_num_units() \
                   and cc not in self.controller.unplaced_services:
                    self.remove_service_widget(cc)
                    continue

            is_required = self.controller.get_charm_state(cc)[0]
            print(is_required)
            if self.show_type == 'required':
                if is_required[0] != CharmState.REQUIRED:
                    self.remove_service_widget(cc)
                    continue
            elif self.show_type == 'non-required':
                if is_required[0] == CharmState.REQUIRED:
                    self.remove_service_widget(cc)
                    continue
                if not cc.allow_multi_units and \
                        cc not in self.controller.unplaced_services:
                    self.remove_service_widget(cc)
                    continue

            sw = self.find_service_widget(cc)
            if sw is None:
                sw = self.add_service_widget(cc)
            sw.update()

in line 17 you're getting just the state from the tuple with the [0] at the end, then in line 20 you're trying to subscript a CharmState enum. you only need one of those subsets. (same issue with 24 as 20)

also I'd rename 'is_required' to 'state', since it isn't a bool