tensor types.
  * **requires_grad** (*bool**, **optional*) -- If autograd should
    record operations on the returned tensor. Default: "False".

Example:
  >>> torch.arange(5)
  tensor([ 0,  1,  2,  3,  4])
  >>> torch.arange(1, 4)
  tensor([ 1,  2,  3])
  >>> torch.arange(1, 2.5, 0.5)
  tensor([ 1.0000,  1.5000,  2.0000])
