remove unused import (pytorch#1501)

Co-authored-by: Holly Sweeney <[email protected]>

Author: idrisr

beginner_source/basics/data_tutorial.py

@@ -48,7 +48,7 @@
 import torch
 from torch.utils.data import Dataset
 from torchvision import datasets
-from torchvision.transforms import ToTensor, Lambda
+from torchvision.transforms import ToTensor
 import matplotlib.pyplot as plt