code: def _load_new(self, img_data: str):
          
          self._image = tk.PhotoImage(data=img_data)
          self._image = self._image.subsample(int(200 / self._size),
                                              int(200 / self._size))
          self._canvas.delete('all')
          self._canvas.create_image(0, 0, image=self._image, anchor='nw')
  
          if self._user_click_callback is not None:
              self._user_click_callback(self._on)
docs: Load a new image.
  
          :param img_data: the image data as a base64 string
          :return: None