def set_state(self, color_hex):
        """
        :param color_hex: a hex string indicating the color of the porkfolio nose
        :return: nothing
        From the api...
        "the color of the nose is not in the desired_state
        but on the object itself."
        """
        root_name = self.json_state.get('piggy_bank_id', self.name())
        response = self.api_interface.set_device_state(self, {
            "nose_color": color_hex
        }, root_name)
        self._update_state_from_response(response)
:param color_hex: a hex string indicating the color of the porkfolio nose
        :return: nothing
        From the api...
        "the color of the nose is not in the desired_state
        but on the object itself."