old_contents: from chainer.functions.activation.elu import elu
  
  
  def selu(x,
           alpha=1.6732632423543772848170429916717,
           scale=1.0507009873554804934193349852946):
      return scale * elu(x, alpha=alpha)
  
new_contents: from chainer.functions.activation.elu import elu
  
  
  def selu(x,
           alpha=1.6732632423543772848170429916717,
           scale=1.0507009873554804934193349852946):
      """Scaled Exponential Linear Unit function.
  
      For parameters :math:`\\alpha` and :math:`\\lambda`, it is expressed as
  
      .. math::
          f(x) = \\lambda \\left \\{ \\begin{array}{ll}
          x & {\\rm if}~ x \\ge 0 \\\\
          \\alpha (\\exp(x) - 1) & {\\rm if}~ x < 0,
          \\end{array} \\right.
  
      See: https://arxiv.org/abs/1706.02515
  
      Args:
          x (:class:`~chainer.Variable` or :class:`numpy.ndarray` or \
          :class:`cupy.ndarray`):
              Input variable. A :math:`(s_1, s_2, ..., s_N)`-shaped float array.
          alpha (float): Parameter :math:`\\alpha`.
          scale (float): Parameter :math:`\\lambda`.
  
      Returns:
          ~chainer.Variable: Output variable. A
          :math:`(s_1, s_2, ..., s_N)`-shaped float array.
  
      """
      return scale * elu(x, alpha=alpha)
  
subject: Add docstring for SELU