<groups>
  <group name="Group A">
    <sender name="Sender 1">
      <traffic_annotation unique_id="unique_id_A"/>
    </sender>
    <sender name="Sender 2">
      <traffic_annotation unique_id="unique_id_B"/>
    </sender>
  </group>
  <group name="Group C">
    <sender name="Sender 3">
      <traffic_annotation unique_id="unique_id_C"/>
    </sender>
  </group>
</groups>