How to use the s3transfer.futures.BoundedExecutor function in s3transfer

self.bucket = 'mybucket'
        self.key = 'mykey'
        self.extra_args = {}
        self.subscribers = []

        # Create a stream to read from
        self.content = b'my content'
        self.stream = six.BytesIO(self.content)

        # A list to keep track of all of the bodies sent over the wire
        # and their order.

        self.call_args = self.get_call_args()
        self.transfer_future = self.get_transfer_future(self.call_args)
        self.io_executor = BoundedExecutor(1000, 1)
        self.submission_main_kwargs = {
            'client': self.client,
            'config': self.config,
            'osutil': self.osutil,
            'request_executor': self.executor,
            'io_executor': self.io_executor,
            'transfer_future': self.transfer_future
        }
        self.submission_task = self.get_download_submission_task()

def setUp(self):
        super(TestSubmissionTask, self).setUp()
        self.executor = BoundedExecutor(1000, 5)
        self.call_args = CallArgs(subscribers=[])
        self.transfer_future = self.get_transfer_future(self.call_args)
        self.main_kwargs = {'transfer_future': self.transfer_future}

def setUp(self):
        super(TestGetObjectTask, self).setUp()
        self.bucket = 'mybucket'
        self.key = 'mykey'
        self.extra_args = {}
        self.callbacks = []
        self.max_attempts = 5
        self.io_executor = BoundedExecutor(1000, 1)
        self.content = b'my content'
        self.stream = six.BytesIO(self.content)
        self.fileobj = WriteCollector()
        self.osutil = OSUtils()
        self.io_chunksize = 64 * (1024 ** 2)
        self.task_cls = GetObjectTask
        self.download_output_manager = DownloadSeekableOutputManager(
            self.osutil, self.transfer_coordinator, self.io_executor)

:param executor_cls: The class of executor to use with the transfer
            manager. By default, concurrent.futures.ThreadPoolExecutor is used.
        """
        self._client = client
        self._config = config
        if config is None:
            self._config = TransferConfig()
        self._osutil = osutil
        if osutil is None:
            self._osutil = OSUtils()
        self._coordinator_controller = TransferCoordinatorController()
        # A counter to create unique id's for each transfer submitted.
        self._id_counter = 0

        # The executor responsible for making S3 API transfer requests
        self._request_executor = BoundedExecutor(
            max_size=self._config.max_request_queue_size,
            max_num_threads=self._config.max_request_concurrency,
            tag_semaphores={
                IN_MEMORY_UPLOAD_TAG: TaskSemaphore(
                    self._config.max_in_memory_upload_chunks),
                IN_MEMORY_DOWNLOAD_TAG: SlidingWindowSemaphore(
                    self._config.max_in_memory_download_chunks)
            },
            executor_cls=executor_cls
        )

        # The executor responsible for submitting the necessary tasks to
        # perform the desired transfer
        self._submission_executor = BoundedExecutor(
            max_size=self._config.max_submission_queue_size,
            max_num_threads=self._config.max_submission_concurrency,

:param executor_cls: The class of executor to use with the transfer
            manager. By default, concurrent.futures.ThreadPoolExecutor is used.
        """
        self._client = client
        self._config = config
        if config is None:
            self._config = TransferConfig()
        self._osutil = osutil
        if osutil is None:
            self._osutil = OSUtils()
        self._coordinator_controller = TransferCoordinatorController()
        # A counter to create unique id's for each transfer submitted.
        self._id_counter = 0

        # The executor responsible for making S3 API transfer requests
        self._request_executor = BoundedExecutor(
            max_size=self._config.max_request_queue_size,
            max_num_threads=self._config.max_request_concurrency,
            tag_semaphores={
                IN_MEMORY_UPLOAD_TAG: TaskSemaphore(
                    self._config.max_in_memory_upload_chunks),
                IN_MEMORY_DOWNLOAD_TAG: SlidingWindowSemaphore(
                    self._config.max_in_memory_download_chunks)
            },
            executor_cls=executor_cls
        )

        # The executor responsible for submitting the necessary tasks to
        # perform the desired transfer
        self._submission_executor = BoundedExecutor(
            max_size=self._config.max_submission_queue_size,
            max_num_threads=self._config.max_submission_concurrency,

# The executor responsible for making S3 API transfer requests
        self._request_executor = BoundedExecutor(
            max_size=self._config.max_request_queue_size,
            max_num_threads=self._config.max_request_concurrency,
            tag_semaphores={
                IN_MEMORY_UPLOAD_TAG: TaskSemaphore(
                    self._config.max_in_memory_upload_chunks),
                IN_MEMORY_DOWNLOAD_TAG: SlidingWindowSemaphore(
                    self._config.max_in_memory_download_chunks)
            },
            executor_cls=executor_cls
        )

        # The executor responsible for submitting the necessary tasks to
        # perform the desired transfer
        self._submission_executor = BoundedExecutor(
            max_size=self._config.max_submission_queue_size,
            max_num_threads=self._config.max_submission_concurrency,
            executor_cls=executor_cls

        )

        # There is one thread available for writing to disk. It will handle
        # downloads for all files.
        self._io_executor = BoundedExecutor(
            max_size=self._config.max_io_queue_size,
            max_num_threads=1,
            executor_cls=executor_cls
        )

        # The component responsible for limiting bandwidth usage if it
        # is configured.

},
            executor_cls=executor_cls
        )

        # The executor responsible for submitting the necessary tasks to
        # perform the desired transfer
        self._submission_executor = BoundedExecutor(
            max_size=self._config.max_submission_queue_size,
            max_num_threads=self._config.max_submission_concurrency,
            executor_cls=executor_cls

        )

        # There is one thread available for writing to disk. It will handle
        # downloads for all files.
        self._io_executor = BoundedExecutor(
            max_size=self._config.max_io_queue_size,
            max_num_threads=1,
            executor_cls=executor_cls
        )

        # The component responsible for limiting bandwidth usage if it
        # is configured.
        self._bandwidth_limiter = None
        if self._config.max_bandwidth is not None:
            logger.debug(
                'Setting max_bandwidth to %s', self._config.max_bandwidth)
            leaky_bucket = LeakyBucket(self._config.max_bandwidth)
            self._bandwidth_limiter = BandwidthLimiter(leaky_bucket)

        self._register_handlers()

},
            executor_cls=executor_cls
        )

        # The executor responsible for submitting the necessary tasks to
        # perform the desired transfer
        self._submission_executor = BoundedExecutor(
            max_size=self._config.max_submission_queue_size,
            max_num_threads=self._config.max_submission_concurrency,
            executor_cls=executor_cls

        )

        # There is one thread available for writing to disk. It will handle
        # downloads for all files.
        self._io_executor = BoundedExecutor(
            max_size=self._config.max_io_queue_size,
            max_num_threads=1,
            executor_cls=executor_cls
        )

        # The component responsible for limiting bandwidth usage if it
        # is configured.
        self._bandwidth_limiter = None
        if self._config.max_bandwidth is not None:
            logger.debug(
                'Setting max_bandwidth to %s', self._config.max_bandwidth)
            leaky_bucket = LeakyBucket(self._config.max_bandwidth)
            self._bandwidth_limiter = BandwidthLimiter(leaky_bucket)

        self._register_handlers()

:param executor_cls: The class of executor to use with the transfer
            manager. By default, concurrent.futures.ThreadPoolExecutor is used.
        """
        self._client = client
        self._config = config
        if config is None:
            self._config = TransferConfig()
        self._osutil = osutil
        if osutil is None:
            self._osutil = OSUtils()
        self._coordinator_controller = TransferCoordinatorController()
        # A counter to create unique id's for each transfer submitted.
        self._id_counter = 0

        # The executor responsible for making S3 API transfer requests
        self._request_executor = BoundedExecutor(
            max_size=self._config.max_request_queue_size,
            max_num_threads=self._config.max_request_concurrency,
            tag_semaphores={
                IN_MEMORY_UPLOAD_TAG: TaskSemaphore(
                    self._config.max_in_memory_upload_chunks),
                IN_MEMORY_DOWNLOAD_TAG: SlidingWindowSemaphore(
                    self._config.max_in_memory_download_chunks)
            },
            executor_cls=executor_cls
        )

        # The executor responsible for submitting the necessary tasks to
        # perform the desired transfer
        self._submission_executor = BoundedExecutor(
            max_size=self._config.max_submission_queue_size,
            max_num_threads=self._config.max_submission_concurrency,

# The executor responsible for making S3 API transfer requests
        self._request_executor = BoundedExecutor(
            max_size=self._config.max_request_queue_size,
            max_num_threads=self._config.max_request_concurrency,
            tag_semaphores={
                IN_MEMORY_UPLOAD_TAG: TaskSemaphore(
                    self._config.max_in_memory_upload_chunks),
                IN_MEMORY_DOWNLOAD_TAG: SlidingWindowSemaphore(
                    self._config.max_in_memory_download_chunks)
            },
            executor_cls=executor_cls
        )

        # The executor responsible for submitting the necessary tasks to
        # perform the desired transfer
        self._submission_executor = BoundedExecutor(
            max_size=self._config.max_submission_queue_size,
            max_num_threads=self._config.max_submission_concurrency,
            executor_cls=executor_cls

        )

        # There is one thread available for writing to disk. It will handle
        # downloads for all files.
        self._io_executor = BoundedExecutor(
            max_size=self._config.max_io_queue_size,
            max_num_threads=1,
            executor_cls=executor_cls
        )

        # The component responsible for limiting bandwidth usage if it
        # is configured.