code: def __init__(self):
      self.metric_data = {}
  
imports: import abc
  import unittest.mock
  from torch.distributed.elastic.metrics.api import MetricData, MetricHandler, MetricStream, _get_metric_name, prof
  from torch.testing._internal.common_utils import run_tests, TestCase
label_desc: Use image node_id 1 to create a new TestMetricsHandler object from inherited base classes: MetricHandler with example: obj = TestMetricsHandler()