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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 _process_from_queue(self, queue):
 """ Internal method to process a task batch from the given queue. Args: queue: Queue name to be processed Returns: Task IDs: List of tasks that were processed (even if there was an error so that client code can assume the queue is empty if nothing was returned) Count: The number of tasks that were attempted to be executed or -1 if the queue lock couldn't be acquired. """

        now = time.time()

        log = self.log.bind(queue=queue)

        batch_size = self._get_queue_batch_size(queue)

        queue_lock, failed_to_acquire = self._get_queue_lock(queue, log)
        if failed_to_acquire:
            return [], -1

        # Move an item to the active queue, if available.
        # We need to be careful when moving unique tasks: We currently don't
        # support concurrent processing of multiple unique tasks. If the task
        # is already in the ACTIVE queue, we need to execute the queued task
        # later, i.e. move it to the SCHEDULED queue (prefer the earliest
        # time if it's already scheduled). We want to make sure that the last
        # queued instance of the task always gets executed no earlier than it
        # was queued.
        later = time.time() + self.config['LOCK_RETRY']

        task_ids = self.scripts.zpoppush(
            self._key(QUEUED, queue),
            self._key(ACTIVE, queue),
            batch_size,
            None,
            now,
            if_exists=('add', self._key(SCHEDULED, queue), later, 'min'),
            on_success=('update_sets', queue, self._key(QUEUED),
                        self._key(ACTIVE), self._key(SCHEDULED))
        )
        log.debug('moved tasks', src_queue=QUEUED, dest_queue=ACTIVE,
                  qty=len(task_ids))

        processed_count = 0
        if task_ids:
            processed_count = self._process_queue_tasks(queue, queue_lock,
                                                        task_ids, now, log)

        if queue_lock:
            queue_lock.release()
            log.debug('released swq lock')

        return task_ids, processed_count