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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 left_release(self, event):
 """ Callback for the release of the left button. :param event: Tkinter event """

        self.config(cursor="")
        if len(self.canvas.find_withtag("current")) != 0 and self.current is not None:
            self.canvas.itemconfigure(tk.CURRENT, fill=self.item_colors[self.current][1])