<models xmlns:xi="http://www.w3.org/2001/XInclude">
  <model name="NOR">
    <input_ports>
      <port name="A" combinational_sink_ports="Y"/>
      <port name="B" combinational_sink_ports="Y"/>
    </input_ports>
    <output_ports>
      <port name="Y"/>
    </output_ports>
  </model>
</models>