code: def set_background(self, image=None, path=None, resize=True):
          
          if not image and not path:
              raise ValueError("You must either pass a PhotoImage object or a path object")
          if image and path:
              raise ValueError("You must pass either a PhotoImage or str path, not both")
          if image is not None and not isinstance(image, tk.PhotoImage) and not isinstance(image, ImageTk.PhotoImage):
              raise ValueError("The image passed is not a PhotoImage object")
          if path is not None and not isinstance(path, str):
              raise ValueError("The image path passed is not of str type: {0}".format(path))
          if path and not os.path.exists(path):
              raise ValueError("The image path passed is not valid: {0}".format(path))
          if image is not None:
              self._image = image
          elif path is not None:
              img = Image.open(path)
              if resize:
                  img = img.resize((self._canvaswidth, self._canvasheight), Image.ANTIALIAS)
              self._image = ImageTk.PhotoImage(img)
          self._background = self.canvas.create_image(0, 0, image=self._image, anchor=tk.NW, tag="background")
          self.canvas.tag_lower("background")
docs: Set the background image of the Canvas.
          
          :param image: background image
          :type image: PhotoImage
          :param path: background image path
          :type path: str
          :param resize: whether to resize the image to the Canvas size
          :type resize: bool