text: from torchvision import datasets
  from .data_loader import DatasetParams
  from .data_loader import register_dataset_obj, register_data_params
  
  @register_data_params('mnist')
  class MNIStParams(DatasetParams):
      
      num_channels = 1
      image_size   = 28
      #mean         = 0.1307
      #std          = 0.3081
      mean = 0.5
      std = 0.5
      num_cls      = 10
  
  @register_dataset_obj('mnist')
  class MNIST(datasets.MNIST):
      def __init__(self, root, train=True,
              transform=None, target_transform=None, download=False):
          super(MNIST, self).__init__(root, train=train, transform=transform,
                  target_transform=target_transform, download=download)
  