code: def test_local_session(self):
      init_net = core.Net("init")
      src_values = Struct(
          ("uid", np.array([1, 2, 6])),
          ("value", np.array([1.4, 1.6, 1.7])),
      )
      expected_dst = Struct(
          ("uid", np.array([2, 4, 12])),
          ("value", np.array([0.0, 0.0, 0.0])),
      )
  
      with core.NameScope("init"):
          src_blobs = NewRecord(init_net, src_values)
          dst_blobs = InitEmptyRecord(
              init_net, src_values.clone_schema()
          )
  
      def proc1(rec):
          net = core.Net("proc1")
          with core.NameScope("proc1"):
              out = NewRecord(net, rec)
          net.Add([rec.uid(), rec.uid()], [out.uid()])
          out.value.set(blob=rec.value(), unsafe=True)
          return [net], out
  
      def proc2(rec):
          net = core.Net("proc2")
          with core.NameScope("proc2"):
              out = NewRecord(net, rec)
          out.uid.set(blob=rec.uid(), unsafe=True)
          net.Sub([rec.value(), rec.value()], [out.value()])
          return [net], out
  
      src_ds = Dataset(src_blobs)
      dst_ds = Dataset(dst_blobs)
  
      with TaskGroup() as tg:
          out1 = pipe(src_ds.reader(), processor=proc1)
          out2 = pipe(out1, processor=proc2)
          pipe(out2, dst_ds.writer())
  
      ws = workspace.C.Workspace()
      FeedRecord(src_blobs, src_values, ws)
      session = LocalSession(ws)
      session.run(init_net)
      session.run(tg)
      output = FetchRecord(dst_blobs, ws=ws)
  
      for a, b in zip(output.field_blobs(), expected_dst.field_blobs()):
          np.testing.assert_array_equal(a, b)
  
file_path: pytorch/caffe2/python/session_test.py
imports: from caffe2.python.schema import Struct, FetchRecord, NewRecord, FeedRecord, InitEmptyRecord
  from caffe2.python import core, workspace
  from caffe2.python.session import LocalSession
  from caffe2.python.dataset import Dataset
  from caffe2.python.pipeline import pipe
  from caffe2.python.task import TaskGroup
  from caffe2.python.test_util import TestCase
  import numpy
label_desc: Use image node_id 1 for calling the TestLocalSession obj's underlying member method code with example usage: obj.test_local_session() and returns: list,  out, list,  out