elements.
     * **inverse_indices** (*Tensor*): (optional) if
       "return_inverse" is True, there will be an additional
       returned tensor (same shape as input) representing the
       indices for where elements in the original input map to in
       the output; otherwise, this function will only return a
       single tensor.

     * **counts** (*Tensor*): (optional) if "return_counts" is
       True, there will be an additional returned tensor (same
       shape as output or output.size(dim), if dim was specified)
       representing the number of occurrences for each unique
       value or tensor.

Return type:
      (Tensor, Tensor (optional), Tensor (optional))
Example:
  >>> x = torch.tensor([1, 1, 2, 2, 3, 1, 1, 2])
  >>> output = torch.unique_consecutive(x)
  >>> output
  tensor([1, 2, 3, 1, 2])

  >>> output, inverse_indices = torch.unique_consecutive(x, return_inverse=True)
  >>> output
