How to use the gradio.networking.close_server function in gradio

Standard method shared by interfaces that creates the interface and sets up a websocket to communicate with it.
        :param inline: boolean. If True, then a gradio interface is created inline (e.g. in jupyter or colab notebook)
        :param inbrowser: boolean. If True, then a new browser window opens with the gradio interface.
        :param share: boolean. If True, then a share link is generated using ngrok is displayed to the user.
        :param validate: boolean. If True, then the validation is run if the interface has not already been validated.
        """
        if validate and not self.validate_flag:
            self.validate()

        # If an existing interface is running with this instance, close it.
        if self.status == self.STATUS_TYPES["RUNNING"]:
            if self.verbose:
                print("Closing existing server...")
            if self.simple_server is not None:
                try:
                    networking.close_server(self.simple_server)
                except OSError:
                    pass

        output_directory = tempfile.mkdtemp()
        # Set up a port to serve the directory containing the static files with interface.
        server_port, httpd = networking.start_simple_server(self, output_directory)
        path_to_local_server = "http://localhost:{}/".format(server_port)
        networking.build_template(
            output_directory, self.input_interface, self.output_interface
        )

        networking.set_interface_types_in_config_file(
            output_directory,
            self.input_interface.__class__.__name__.lower(),
            self.output_interface.__class__.__name__.lower(),
        )

Standard method shared by interfaces that creates the interface and sets up a websocket to communicate with it.
        :param inline: boolean. If True, then a gradio interface is created inline (e.g. in jupyter or colab notebook)
        :param inbrowser: boolean. If True, then a new browser window opens with the gradio interface.
        :param share: boolean. If True, then a share link is generated using ngrok is displayed to the user.
        :param validate: boolean. If True, then the validation is run if the interface has not already been validated.
        """
        if validate and not self.validate_flag:
            self.validate()

        # If an existing interface is running with this instance, close it.
        if self.status == self.STATUS_TYPES["RUNNING"]:
            if self.verbose:
                print("Closing existing server...")
            if self.simple_server is not None:
                try:
                    networking.close_server(self.simple_server)
                except OSError:
                    pass

        output_directory = tempfile.mkdtemp()
        # Set up a port to serve the directory containing the static files with interface.
        server_port, httpd = networking.start_simple_server(self, output_directory)
        path_to_local_server = "http://localhost:{}/".format(server_port)
        networking.build_template(
            output_directory, self.input_interface, self.output_interface
        )

        self.update_config_file(output_directory)

        self.status = self.STATUS_TYPES["RUNNING"]
        self.simple_server = httpd