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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def is_skorch_dataset(ds):
 """Checks if the supplied dataset is an instance of ``skorch.dataset.Dataset`` even when it is nested inside ``torch.util.data.Subset``."""

    from skorch.dataset import Dataset
    if isinstance(ds, Subset):
        return is_skorch_dataset(ds.dataset)
    return isinstance(ds, Dataset)