code: def backend_gpu(request):
      """
      Fixture to setup the backend before running a test.  Also registers the teardown function to
      clean up the backend after a test is done.  This has module scope, so this will be run once
      for each test in a given test file (module).
  
      This fixture is parameterized to run both the cpu and gpu backends for every test
      """
      be = get_backend(request)
  
      # add a cleanup call - will run after all test in module are done
      def cleanup():
          be = request.getfuncargvalue("backend_gpu")
          del be
  
      request.addfinalizer(cleanup)
  
      # tests using this fixture can access the backend object from
      # backend or use the NervanaObject.be global
      return be
  
imports: import itertools
  import numpy
  import pytest
  import re
  import os
  import sys
  from neon.backends import gen_backend
  from neon.backends.nervanacpu import NervanaCPU
  from neon.layers.container import DeltasTree
label_desc: Use image node_id 6 for calling a global function with example usage: backend_gpu(request) and returns: be