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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 remove_all_callbacks(self):
 """ Removes all registered callbacks."""

        for cb_id in list(self._next_tick_callback_removers.keys()):
            self.remove_next_tick_callback(cb_id)
        for cb_id in list(self._timeout_callback_removers.keys()):
            self.remove_timeout_callback(cb_id)
        for cb_id in list(self._periodic_callback_removers.keys()):
            self.remove_periodic_callback(cb_id)