code: def test_metadata(self):
      pb = self.compute_and_check_summary_pb(
          name="foo",
          labels=np.array([True]),
          predictions=np.float32([0.42]),
          num_thresholds=3,
      )
      summary_metadata = pb.value[0].metadata
      plugin_data = summary_metadata.plugin_data
      self.assertEqual("foo", summary_metadata.display_name)
      self.assertEqual("", summary_metadata.summary_description)
      self.assertEqual(metadata.PLUGIN_NAME, plugin_data.plugin_name)
      plugin_data = metadata.parse_plugin_metadata(
          summary_metadata.plugin_data.content
      )
      self.assertEqual(3, plugin_data.num_thresholds)
  
imports: import numpy
  import tensorflow
  from tensorboard.compat.proto import summary_pb2
  from tensorboard.plugins.pr_curve import metadata
  from tensorboard.plugins.pr_curve import summary
  from tensorboard.util import tensor_util
  from tensorboard.util import test_util
label_desc: Use image node_id 6 for calling the PrCurveTest obj's underlying member method code with example usage: obj.test_metadata() without return types