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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 wait_for_batches(self, batch_ids, timeout=None):
 """Locks until a list of batch ids is committed to the block chain or a timeout is exceeded. Returns the statuses of those batches. Args: batch_ids (list of str):
 The ids of the batches to wait for timeout(int):
 Maximum time in seconds to wait for Returns: list of BatchStatus: BatchStatuses to send back to client """

        self._batch_tracker.watch_statuses(self, batch_ids)
        timeout = timeout or DEFAULT_TIMEOUT
        start_time = time()

        with self._wait_condition:
            while True:
                if self._statuses is not None:
                    return _format_batch_statuses(
                        self._statuses, batch_ids, self._batch_tracker)

                if time() - start_time > timeout:
                    statuses = self._batch_tracker.get_statuses(batch_ids)
                    return _format_batch_statuses(
                        statuses, batch_ids, self._batch_tracker)

                self._wait_condition.wait(timeout - (time() - start_time))