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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 connected_client(self):
 """Returns a ContextManagerFuture to be yielded in a with statement. Returns: A ContextManagerFuture object. Examples: # client is a connected tornadis.Client instance # it will be automatically released to the pool thanks to # the "with" keyword reply = yield client.call("PING") """

        future = self.get_connected_client()
        cb = functools.partial(self._connected_client_release_cb, future)
        return ContextManagerFuture(future, cb)