 ...         if worker_info is None:  # single-process data loading, return the full iterator
        ...             iter_start = self.start
        ...             iter_end = self.end
        ...         else:  # in a worker process
        ...             # split workload
        ...             per_worker = int(math.ceil((self.end - self.start) / float(worker_info.num_workers)))
        ...             worker_id = worker_info.id
        ...             iter_start = self.start + worker_id * per_worker
        ...             iter_end = min(iter_start + per_worker, self.end)
        ...         return iter(range(iter_start, iter_end))
        ...
        >>> # should give same set of data as range(3, 7), i.e., [3, 4, 5, 6].
        >>> ds = MyIterableDataset(start=3, end=7)

        >>> # Single-process loading
        >>> print(list(torch.utils.data.DataLoader(ds, num_workers=0)))
        [tensor([3]), tensor([4]), tensor([5]), tensor([6])]

        >>> # xdoctest: +REQUIRES(POSIX)
        >>> # Mult-process loading with two worker processes
        >>> # Worker 0 fetched [3, 4].  Worker 1 fetched [5, 6].
        >>> # xdoctest: +IGNORE_WANT("non deterministic")
        >>> print(list(torch.utils.data.DataLoader(ds, num_workers=2)))
        [tensor([3]), tensor([5]), tensor([4]), tensor([6])]

        >>> # With even more workers
        >>> # xdoctest: +IGNORE_WANT("non deterministic")
        >>> print(list(torch.utils.data.DataLoader(ds, num_workers=12)))
        [tensor([3]), tensor([5]), tensor([4]), tensor([6])]

    Example 2: splitting workload across all workers using :attr:`worker_init_fn`::

        >>> # xdoctest: +REQUIRES(env:TORCH_DOCTEST_DATALOADER)
        >>> class MyIterableDataset(torch.utils.data.IterableDataset):
        ...     def __init__(self, start, end):
        ...         super(MyIterableDataset).__init__()
        ...         assert end > start, "this example code only works with end >= start"
        ...         self.start = start
        ...         self.end = end
        ...
        ...     def __iter__(self):
        ...         return iter(range(self.start, self.end))
        ...
        >>> # should give same set of data as range(3, 7), i.e., [3, 4, 5, 6].
        >>> ds = MyIterableDataset(start=3, end=7)

        >>> # Single-process loading
        >>> print(list(torch.utils.data.DataLoader(ds, num_workers=0)))
        [3, 4, 5, 6]
        >>>
        >>> # Directly doing multi-process loading yields duplicate data
        >>> print(list(torch.utils.data.DataLoader(ds, num_workers=2)))
        [3, 3, 4, 4, 5, 5, 6, 6]

        >>> # Define a `worker_init_fn` that configures each dataset copy differently
        >>> def worker_init_fn(worker_id):
        ...     worker_info = torch.utils.data.get_worker_info()
        ...     dataset = worker_info.dataset  # the dataset copy in this worker process
        ...     overall_start = dataset.start
        ...     overall_end = dataset.end
        ...     # configure the dataset to only process the split workload
        ...     per_worker = int(math.ceil((overall_end - overall_start) / float(worker_info.num_workers)))
        ...     worker_id = worker_info.id
        ...     dataset.start = overall_start + worker_id * per_worker
        ...     dataset.end = min(dataset.start + per_worker, overall_end)
        ...

        >>> # Mult-process loading with the custom `worker_init_fn`
        >>> # Worker 0 fetched [3, 4].  Worker 1 fetched [5, 6].
        >>> print(list(torch.utils.data.DataLoader(ds, num_workers=2, worker_init_fn=worker_init_fn)))
        [3, 5, 4, 6]

        >>> # With even more workers
        >>> print(list(torch.utils.data.DataLoader(ds, num_workers=12, worker_init_fn=worker_init_fn)))
        [3, 4, 5, 6]
    r