code: def __init__(self, name):
      def shared(x, **kwargs):
          return gpuarray_shared_constructor(
              x, target=test_ctx_name, **kwargs
          )
  
      test_subtensor.T_subtensor.__init__(
          self,
          name,
          shared=shared,
          sub=GpuSubtensor,
          inc_sub=GpuIncSubtensor,
          adv_sub1=GpuAdvancedSubtensor1,
          adv_incsub1=GpuAdvancedIncSubtensor1,
          adv_sub=GpuAdvancedSubtensor,
          adv_bool_sub=GpuAdvancedBooleanSubtensor,
          dimshuffle=GpuDimShuffle,
          mode=mode_with_gpu,
          # avoid errors with limited devices
          dtype="float16",  # use floatX?
          ignore_topo=(
              HostFromGpu,
              GpuFromHost,
              DeepCopyOp,
              GpuContiguous,
          ),
      )
      # GPU opt can't run in fast_compile only.
      self.fast_compile = False
      assert self.sub == GpuSubtensor
  
imports: from __future__ import absolute_import, print_function, division
  import numpy
  import unittest
  import theano
  from theano import tensor
  from theano.compile import DeepCopyOp
  from theano.tensor.tests import test_subtensor, test_basic
  from theano.tests import unittest_tools
  from ..basic_ops import HostFromGpu, GpuFromHost, GpuContiguous
  from ..elemwise import GpuDimShuffle
  from ..subtensor import GpuIncSubtensor, GpuSubtensor, GpuAdvancedSubtensor1, GpuAdvancedSubtensor, GpuAdvancedBooleanSubtensor, GpuAdvancedIncSubtensor, GpuAdvancedIncSubtensor1, GpuAdvancedIncSubtensor1_dev20, GpuExtractDiag, GpuAllocDiag
  from ..type import gpuarray_shared_constructor
  from .config import mode_with_gpu, test_ctx_name
label_desc: Use image node_id 2 to create a new G_subtensorF16 object from inherited base classes: test_subtensor with example: obj = G_subtensorF16(name)