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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 _get_avaliable_tasks(self):
 """Get all tasks present in the queue."""

        base_task = posixpath.join(self._queue_path, self.TASK_PREFIX)
        tasks = self._client.kv.find(prefix=base_task)
        return sorted(tasks.items())