docstr: Test that Reload() means GetSourceWriter() won't load events.
code: def testReloadPopulatesSourceWriter(self):
      """Test that Reload() means GetSourceWriter() won't load events."""
      gen = _EventGenerator(self)
      acc = ea.EventAccumulator(gen)
      gen.AddEvent(
          event_pb2.Event(
              wall_time=1,
              step=2,
              source_metadata=event_pb2.SourceMetadata(
                  writer="custom_writer"
              ),
          )
      )
      acc.Reload()
  
      def _Die(*args, **kwargs):  # pylint: disable=unused-argument
          raise RuntimeError("Load() should not be called")
  
      self.stubs.Set(gen, "Load", _Die)
      self.assertEqual(acc.GetSourceWriter(), "custom_writer")
  
imports: import os
  import numpy
  import tensorflow
  from tensorboard.backend.event_processing import event_accumulator
  from tensorboard.compat.proto import config_pb2
  from tensorboard.compat.proto import event_pb2
  from tensorboard.compat.proto import graph_pb2
  from tensorboard.compat.proto import meta_graph_pb2
  from tensorboard.compat.proto import summary_pb2
  from tensorboard.plugins.distribution import compressor
  from tensorboard.util import tensor_util
  from tensorboard.util import test_util
  from tensorboard.util import tb_logging
label_desc: Use image node_id 22 for calling the MockingEventAccumulatorTest obj's underlying member method code with example usage: obj.testReloadPopulatesSourceWriter() without return types