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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 update_active(self):
 """Update the active marker on the marker Canvas"""

        if self.active is not None:
            self.update_state(self.active, "normal")
        if self.current_iid == self.active:
            self._active = None
            return
        self._active = self.current_iid
        if self.active is not None:
            self.update_state(self.active, "active")