"\(in Python v3.8\)") _,_ _optional_ ) – If ` True  ` (default), sampler will shuffle the indices. 

  * **seed** ( [ _int_ ](https://docs.python.org/3/library/functions.html#int "\(in Python v3.8\)") _,_ _optional_ ) – random seed used to shuffle the sampler if ` shuffle=True  ` . This number should be identical across all processes in the distributed group. Default: ` 0  ` . 

Warning

In distributed mode, calling the :meth`set_epoch(epoch) <set_epoch>` method at
the beginning of each epoch **before** creating the ` DataLoader  ` iterator
is necessary to make shuffling work properly across multiple epochs.
Otherwise, the same ordering will be always used.

Example:

    
    
    >>> sampler = DistributedSampler(dataset) if is_distributed else None
    >>> loader = DataLoader(dataset, shuffle=(sampler is None),
    ...                     sampler=sampler)
    >>> for epoch in range(start_epoch, n_epochs):
    ...     if is_distributed:
    ...         sampler.set_epoch(epoch)
    ...     train(loader)
    

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