indices for where elements in the original input ended up in
        the returned unique list.
  * **return_counts** (*bool*) -- Whether to also return the
    counts for each unique element.

  * **dim** (*int*) -- the dimension to apply unique. If "None",
    the unique of the flattened input is returned. default: "None"

Returns:
      A tensor or a tuple of tensors containing
     * **output** (*Tensor*): the output list of unique scalar
       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
