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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 _disconnected(self, uri):
 """Disconnected callback from Crazyflie API"""

        self.param_updater.close()
        self.is_updated = False
        # Clear all values from the previous Crazyflie
        self.toc = Toc()
        self.values = {}