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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 delete_marker(self, iid):
 """ Delete a marker from the TimeLine :param iid: marker identifier :type iid: str """

        if iid == tk.ALL:
            for iid in self.markers.keys():
                self.delete_marker(iid)
            return
        options = self._markers[iid]
        rectangle_id, text_id = options["rectangle_id"], options["text_id"]
        del self._canvas_markers[rectangle_id]
        del self._canvas_markers[text_id]
        del self._markers[iid]
        self._timeline.delete(rectangle_id, text_id)