title: Python, Tkinter: How to get the handle of all canvas objects using their IDs or tags?
body: <p>I would like get the handles of all rectangles on a canvas with a certain tag to place them with the grid geometry manager (the user can move them around by mouse-dragging and then I would like to "reorder" them for him). I do not have the handles of the rectangles, but they all have the same tag ("moveable_canvas"). From there I can convert to the item id (.find_withtag) but what now? The the ID I could to an .itemconfigure etc., but how to "grid" them?</p>
  
  <pre><code>moveable_canvases = self.canv.find_withtag("moveable_canvas")
  for canvas_id in moveable_canvases:
      ???.grid(...)
  </code></pre>