<edges xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="http://sumo.dlr.de/xsd/edges_file.xsd">

   <edge id="oa" from="o" to="a"/>
   <edge id="ab" from="a" to="b"/>
   <edge id="bd" from="b" to="d"/>
   <edge id="ox" from="o" to="x"/>
   <edge id="xy" from="x" to="y"/>
   <edge id="yd" from="y" to="d"/>
   <edge id="ax" from="a" to="x"/>
   <edge id="by" from="b" to="y"/>

</edges>
