def __init__(
        self,
        root: str,
        transform: Optional[Callable] = None,
        gallery_fraq: Optional[float] = 0.2,
        **kwargs
    ) -> None:
        """
        Args:
            root: root directory for storing dataset
            transform: transform
            gallery_fraq: gallery size
        """
        self._cifar = CIFAR10(root, train=False, download=True, transform=transform)
        self._filter()

        self._gallery_size = int(gallery_fraq * len(self._cifar))
        self._query_size = len(self._cifar) - self._gallery_size

        self._is_query = torch.zeros(len(self._cifar)).type(torch.bool)
        self._is_query[: self._query_size] = True

        Args:
            root: root directory for storing dataset
            transform: transform
            gallery_fraq: gallery size
        
catalyst/contrib/datasets/cifar.py