"size_average" and "reduce" are in the process of being
        deprecated, and in the meantime, specifying either of those
        two args will override "reduction". Default: "'mean'"
  * **beta** (*float**, **optional*) -- Specifies the threshold at
    which to change between L1 and L2 loss. The value must be non-
    negative. Default: 1.0

Shape:
      * Input: (*), where * means any number of dimensions.
  * Target: (*), same shape as the input.

  * Output: scalar. If "reduction" is "'none'", then (*), same
    shape as the input.
