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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _generate_graph_controls(self):
 """ Display sidebar controls. i.e. buttons, and controls"""

        # setup mode radio buttons
        stress_modes = self.controller.stress_conroller.get_modes()
        group = []
        for mode in stress_modes:
            self.mode_buttons.append(radio_button(group, mode,
                                                  self.on_mode_button))

        # Set default radio button to "Monitor" mode
        self.mode_buttons[0].set_state(True, do_callback=False)

        # Create list of buttons
        control_options = list()
        control_options.append(button('Graphs',
                                      self.on_graphs_menu_open))
        control_options.append(button('Summaries',
                                      self.on_summary_menu_open))
        if self.controller.stress_exe:
            control_options.append(button('Stress Options',
                                          self.on_stress_menu_open))
        control_options.append(button("Reset", self.on_reset_button))
        control_options.append(button('Help', self.on_help_menu_open))
        control_options.append(button('About', self.on_about_menu_open))
        control_options.append(button("Save Settings",
                                      self.on_save_settings))
        control_options.append(button("Quit", self.on_exit_program))

        # Create the menu
        animate_controls = urwid.GridFlow(control_options, 18, 2, 0, 'center')

        # Create smooth graph selection button
        default_smooth = self.controller.smooth_graph_mode
        if urwid.get_encoding_mode() == "utf8":
            unicode_checkbox = urwid.CheckBox(
                "UTF-8", state=default_smooth,
                on_state_change=self.on_unicode_checkbox)
            # Init the state of the graph accoding to the selected mode
            self.on_unicode_checkbox(state=default_smooth)
        else:
            unicode_checkbox = urwid.Text(
                "[N/A] UTF-8")

        install_stress_message = urwid.Text("")
        if not self.controller.stress_exe:
            install_stress_message = urwid.Text(
                ('button normal', u"(N/A) install stress"))

        controls = [urwid.Text(('bold text', u"Modes"), align="center")]
        controls += self.mode_buttons
        controls += [
            install_stress_message,
            urwid.Text(('bold text', u"Stress Timer"), align="center"),
            self.clock_view,
            urwid.Divider(),
            urwid.Text(('bold text', u"Control Options"), align="center"),
            animate_controls,
            urwid.Divider(),
            urwid.Text(('bold text', u"Visual Options"), align="center"),
            unicode_checkbox,
            self.refresh_rate_ctrl,
            urwid.Divider(),
            urwid.Text(('bold text', u"Summaries"), align="center"),
        ]

        return controls