code: def status_bar(python_input):
      
      TB = 'class:status-toolbar'
  
      @if_mousedown
      def toggle_paste_mode(mouse_event):
          python_input.paste_mode = not python_input.paste_mode
  
      @if_mousedown
      def enter_history(mouse_event):
          python_input.enter_history()
  
      def get_text_fragments():
          python_buffer = python_input.default_buffer
  
          result = []
          append = result.append
  
          append((TB, ' '))
          result.extend(get_inputmode_fragments(python_input))
          append((TB, ' '))
  
          # Position in history.
          append((TB, '%i/%i ' % (python_buffer.working_index + 1,
                                  len(python_buffer._working_lines))))
  
          # Shortcuts.
          app = get_app()
          if not python_input.vi_mode and app.current_buffer == python_input.search_buffer:
              append((TB, '[Ctrl-G] Cancel search [Enter] Go to this position.'))
          elif bool(app.current_buffer.selection_state) and not python_input.vi_mode:
              # Emacs cut/copy keys.
              append((TB, '[Ctrl-W] Cut [Meta-W] Copy [Ctrl-Y] Paste [Ctrl-G] Cancel'))
          else:
              result.extend([
                  (TB + ' class:key', '[F3]', enter_history),
                  (TB, ' History ', enter_history),
                  (TB + ' class:key', '[F6]', toggle_paste_mode),
                  (TB, ' ', toggle_paste_mode),
              ])
  
              if python_input.paste_mode:
                  append((TB + ' class:paste-mode-on', 'Paste mode (on)', toggle_paste_mode))
              else:
                  append((TB, 'Paste mode', toggle_paste_mode))
  
          return result
  
      return ConditionalContainer(
              content=Window(content=FormattedTextControl(get_text_fragments), style=TB),
              filter=~is_done & renderer_height_is_known &
                   Condition(lambda: python_input.show_status_bar and
                                        not python_input.show_exit_confirmation))
docs: Create the `Layout` for the status bar.