class_docstr: Identity activation function, :math:`f(x) = x`
docstr: Returns the input as output.
  
  Arguments:
      x (Tensor or optree): input value
  
  Returns:
      Tensor or optree: identical to input
docstr_tok: ["Returns","the","input","as","output",".","Arguments",":","x","(","Tensor","or","optree",")",":","input","value","Returns",":","Tensor","or","optree",":","identical","to","input"]
code: def __call__(self, x):
      """
      Returns the input as output.
  
      Arguments:
          x (Tensor or optree): input value
  
      Returns:
          Tensor or optree: identical to input
      """
      return x
  
imports: from __future__ import division
  from neon.transforms.transform import Transform
label_desc: Use image node_id 2 for calling the Identity obj's underlying member method code with example usage: obj.__call__(x) and returns: x