RLException: Invalid roslaunch XML syntax: not well-formed (invalid token)

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Hi everyone, I'm trying to launch the turtlebot simulation but I keep getting errors, so I've started to check xacro files and I get XML syntax. The problem is supposed to be in Line 1 column 1, but I do not know how to fix this.

<?xml version="1.0"?>
<robot xmlns:xacro="http://ros.org/wiki/xacro">
  <!-- General -->
  <xacro:include filename="$(find turtlebot_description)/urdf/common_properties.urdf.xacro"/>
  <xacro:include filename="$(find turtlebot_description)/urdf/turtlebot_properties.urdf.xacro"/>
  <!-- Bases -->
  <!--xacro:include filename="$(find create_description)/urdf/create.urdf.xacro"/-->
  <xacro:include filename="$(find kobuki_description)/urdf/kobuki.urdf.xacro" />
  <!-- Stacks -->
  <xacro:include filename="$(find turtlebot_description)/urdf/stacks/circles.urdf.xacro"/>
  <xacro:include filename="$(find kobuki_description)/urdf/stacks/hexagons.urdf.xacro"/>
  <!-- 3D Sensors -->
  <xacro:include filename="$(find kobuki_description)/urdf/sensors/kinect.urdf.xacro"/>
  <xacro:include filename="$(find kobuki_description)/urdf/sensors/asus_xtion_pro.urdf.xacro"/>
  <xacro:include filename="$(find kobuki_description)/urdf/sensors/asus_xtion_pro_offset.urdf.xacro"/>
</robot>

and the response is

RLException: Invalid roslaunch XML syntax: not well-formed (invalid token): line 1, column 1
The traceback for the exception was written to the log file