code: def code_version(version):
      """
      Decorator to support version-based cache mechanism.
  
      """
      if not isinstance(version, tuple):
          raise TypeError("version must be tuple", version)
  
      def deco(f):
          f.code_version = version
          return f
  
      return deco
  
file_path: Theano/theano/gpuarray/kernel_codegen.py
imports: from __future__ import absolute_import, print_function, division
label_desc: Use image node_id 2 for calling a global function with example usage: code_version(version) and returns: deco, f