code: def _run_handler(self, request):
      request_proto = api_pb2.ListMetricEvalsRequest()
      text_format.Merge(request, request_proto)
      handler = list_metric_evals.Handler(
          context.RequestContext(),
          request_proto,
          self._mock_scalars_plugin,
          "exp_id",
      )
      return handler.run()
  
file_path: tensorboard/tensorboard/plugins/hparams/list_metric_evals_test.py
imports: from unittest import mock
  import tensorflow
  from google.protobuf import text_format
  from tensorboard import context
  from tensorboard.plugins.hparams import api_pb2
  from tensorboard.plugins.hparams import list_metric_evals
  from tensorboard.plugins.scalar import scalars_plugin
label_desc: Use image node_id 3 for calling the ListMetricEvalsTest obj's underlying member method code with example usage: obj._run_handler(request) and returns: handler