torch.is_tensor
torch.is_tensor(obj)
Returns True if obj is a PyTorch tensor.
Note that this function is simply doing "isinstance(obj, Tensor)".
   Using that "isinstance" check is better for typechecking with mypy,
   and more explicit - so it's recommended to use that instead of
   "is_tensor".
Parameters:
      obj (Object) -- Object to test
Example:
  >>> x = torch.tensor([1, 2, 3])
  >>> torch.is_tensor(x)
  True
