code: def test_transfer_gpu_gpu():
      g = GpuArrayType(
          dtype="float32",
          broadcastable=(False, False),
          context_name=test_ctx_name,
      )()
  
      av = np.asarray(rng.rand(5, 4), dtype="float32")
      gv = gpuarray.array(av, context=get_context(test_ctx_name))
      mode = mode_with_gpu.excluding(
          "cut_gpua_host_transfers", "local_cut_gpua_host_gpua"
      )
      f = theano.function([g], GpuToGpu(test_ctx_name)(g), mode=mode)
      topo = f.maker.fgraph.toposort()
      assert len(topo) == 1
      assert isinstance(topo[0].op, GpuToGpu)
      fv = f(gv)
      assert GpuArrayType.values_eq(fv, gv)
  
imports: from __future__ import absolute_import, print_function, division
  import unittest
  from theano.compat import izip
  from six import iteritems
  import numpy
  import theano
  import theano.tensor
  from theano.tensor import TensorType
  from theano.tensor.basic import alloc
  from theano.tensor.tests import test_basic
  from theano.tensor.tests.test_basic import rand, safe_make_node
  from theano.tests import unittest_tools
  from ..type import GpuArrayType, get_context, gpuarray_shared_constructor
  from ..basic_ops import host_from_gpu, HostFromGpu, GpuFromHost, GpuReshape, GpuToGpu, GpuAlloc, GpuAllocEmpty, GpuContiguous, gpu_join, GpuJoin, GpuSplit, GpuEye, GpuTri, gpu_contiguous
  from ..elemwise import GpuDimShuffle, GpuElemwise
  from ..subtensor import GpuSubtensor
  from .config import mode_with_gpu, mode_without_gpu, test_ctx_name
  from pygpu import gpuarray
label_desc: Use image node_id 6 for calling a global function with example usage: test_transfer_gpu_gpu() without return types