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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _extract_device_name_from_event(event):
 """Extract device name from a tf.Event proto carrying tensor value."""

  plugin_data_content = json.loads(
      tf.compat.as_str(event.summary.value[0].metadata.plugin_data.content))
  return plugin_data_content['device']