code: def get_identifier(identifier, module_globals, module_name):
      """Helper utility to retrieve the callable function associated with a string identifier.
  
      Args:
          identifier: The identifier. Could be a string or function.
          module_globals: The global objects of the module.
          module_name: The module name
  
      Returns:
          The callable associated with the identifier.
      """
      if isinstance(identifier, six.string_types):
          fn = module_globals.get(identifier)
          if fn is None:
              raise ValueError(
                  "Unknown {}: {}".format(module_name, identifier)
              )
          return fn
      elif callable(identifier):
          return identifier
      else:
          raise ValueError("Could not interpret identifier")
  
imports: from __future__ import absolute_import
  from __future__ import division
  import os
  import tempfile
  import math
  import json
  import six
  import numpy
  import matplotlib.font_manager
  from skimage import io, transform
  from keras import backend
  from keras.models import load_model
  import logging
label_desc: Use image node_id 6 for calling a global function with example usage: get_identifier(identifier, module_globals, module_name) and returns: fn, identifier