This is a duplicate question of another one in ROS answers, see here: https://answers.ros.org/question/235053/why-cant-i-roslaunch/

I ran into this error when running a launch file called turtlemimic.launch

This is the error I received when attempting to run the file in the terminal:

Invalid roslaunch XML syntax: syntax error: line 1, column 3
The traceback for the exception was written to the log file

This is the XML code for the launch file:

       1 <launch>
       2 
       3   <group ns="turtlesim1">
       4     <node pkg="turtlesim" name="sim" type="turtlesim_node"/>
       5   </group>
       6 
       7   <group ns="turtlesim2">
       8     <node pkg="turtlesim" name="sim" type="turtlesim_node"/>
       9   </group>
      10 
      11   <node pkg="turtlesim" name="mimic" type="mimic">
      12     <remap from="input" to="turtlesim1/turtle1"/>
      13     <remap from="output" to="turtlesim2/turtle1"/>
      14   </node>
      15 
      16 </launch>

Any advice on how to fix this issue would be greatly appreciated. Thanks!