Remove obsolete import (#2059)

Author: Pseudomanifold

beginner_source/basics/optimization_tutorial.py

@@ -28,7 +28,7 @@
 from torch import nn
 from torch.utils.data import DataLoader
 from torchvision import datasets
-from torchvision.transforms import ToTensor, Lambda
+from torchvision.transforms import ToTensor
 
 training_data = datasets.FashionMNIST(
     root="data",