code: def testGraphCollectionAfterDevicePlacement(self):
      @def_function.function
      def f(x):
          return x + constant_op.constant(1.0)
  
      with context.collect_graphs() as graphs:
          with ops.device("CPU:0"):
              f(constant_op.constant(1.0))
  
      self.assertLen(graphs, 1)
      (graph,) = graphs
      self.assertIn("CPU:0", graph.node[0].device)
  
imports: import weakref
  from absl.testing import parameterized
  import numpy
  from xla.service import hlo_pb2
  from tensorflow.python.eager import context
  from tensorflow.python.eager import def_function
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.platform import test
label_desc: Use image node_id 4 for calling the ContextTest obj's underlying member method code with example usage: obj.testGraphCollectionAfterDevicePlacement() and returns: unknown