jetson agx xavier +ros+python

<launch>
 <node name="talker"pkg="beginner_tutorials"type="talker.py"/>
 <node name="listener"pkg="beginner_tutorials"type="listener.py"/>
</launch>

RLException: Invalid roslaunch XML syntax: not well-formed (invalid token): line 2, column 20
The traceback for the exception was written to the log file

<launch>
    <node name="talker" pkg="beginner_tutorials" type="talker.py" />
    <node name="listener" pkg="beginner_tutorials" type="listener.py" />
</launch>