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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 until_state(self, state, timeout=None):
 """Future that resolves when a certain client state is attained Parameters state : str Desired state, one of ("disconnected", "syncing", "synced") timeout: float Timeout for operation in seconds. """

        return self._state.until_state(state, timeout=timeout)