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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_click(self, event):
 """Function bound to left click event for marker canvas"""

        self.update_active()
        iid = self.current_iid
        if iid is None:
            return
        args = (iid, event.x_root, event.y_root)
        self.call_callbacks(iid, "left_callback", args)