torch.flip
torch.flip(input, dims) -> Tensor
Reverse the order of an n-D tensor along given axis in dims.
Note:
 *torch.flip* makes a copy of "input"'s data. This is different
 from NumPy's *np.flip*, which returns a view in constant time.
 Since copying a tensor's data is more work than viewing that
 data, *torch.flip* is expected to be slower than *np.flip*.

Parameters:
      * input (Tensor) -- the input tensor.
  * **dims** (*a list** or **tuple*) -- axis to flip on

Example:
  >>> x = torch.arange(8).view(2, 2, 2)
  >>> x
  tensor([[[ 0,  1],
           [ 2,  3]],

          [[ 4,  5],
           [ 6,  7]]])
  >>> torch.flip(x, [0, 1])
  tensor([[[ 6,  7],
           [ 4,  5]],

          [[ 2,  3],
           [ 0,  1]]])
