code: def test_pdbbreakpoint_op():
      # Test that PdbBreakpoint ops don't block gpu optimization
      b = tensor.fmatrix()
  
      # Create a function composed of a breakpoint followed by
      # some computation
      condition = tensor.gt(b.sum(), 0)
      b_monitored = PdbBreakpoint(name="TestBreakpoint")(condition, b)
      output = b_monitored**2
  
      f = theano.function([b], output, mode=mode_with_gpu)
  
      # Ensure that, in the compiled function, the computation following the
      # breakpoint has been moved to the gpu.
      topo = f.maker.fgraph.toposort()
      assert isinstance(topo[-2].op, GpuElemwise)
      assert topo[-1].op == host_from_gpu
      assert _check_stack_trace(f)
  
imports: from __future__ import absolute_import, print_function, division
  from nose.tools import assert_raises
  import numpy
  import theano
  from theano import tensor
  import theano.tensor.slinalg
  from theano.tests.breakpoint import PdbBreakpoint
  from theano.tests import unittest_tools, test_ifelse
  from theano.tensor.tests import test_basic
  from theano.gof.opt import check_stack_trace
  import theano.gpuarray
  from ..None import basic_ops
  from ..type import GpuArrayType, gpuarray_shared_constructor, get_context
  from ..basic_ops import GpuAlloc, GpuAllocEmpty, GpuReshape, GpuFromHost, HostFromGpu, host_from_gpu
  from ..blas import GpuGemm
  from ..elemwise import GpuCAReduceCuda, GpuCAReduceCPY, GpuElemwise, Elemwise, max_inputs_to_GpuElemwise
  from ..dnn import GpuDnnReduction
  from ..subtensor import GpuSubtensor
  from ..linalg import GpuCusolverSolve, cusolver_available, GpuCholesky
  from .config import mode_with_gpu, mode_without_gpu, test_ctx_name, SkipTest
  import unittest
  from theano.tensor.nnet import abstract_conv
  from theano.gpuarray import dnn, blas, opt
label_desc: Use image node_id 12 for calling a global function with example usage: test_pdbbreakpoint_op() without return types