Basics Tensors tutorial needs to explain tensor.T

[rlaferla]

There is no explanation of what ".T" means/does. Furthermore, there needs to be sample input/output data.

https://pytorch.org/tutorials/beginner/basics/tensor_tutorial.html

# This computes the matrix multiplication between two tensors. y1, y2, y3 will have the same value
y1 = tensor @ tensor.T
y2 = tensor.matmul(tensor.T)

y3 = torch.rand_like(tensor)
torch.matmul(tensor, tensor.T, out=y3)