code: def _identity(x):
      return x
  
file_path: keras-vis/vis/optimizer.py
imports: from __future__ import absolute_import
  import numpy
  from keras import backend
  from .callbacks import Print
  from .grad_modifiers import get
  from .utils import utils
label_desc: Use image node_id 1 for calling a global function with example usage: _identity(x) and returns: x