Invalid roslaunch XML syntax: no root <launch> tag

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I was trying to launch a file and I am getting this error every time, I was trying to use the turtlebot3 map in my different robot. so I copied turtlebot3_house.world to my robot workspace.

<?xml version="1.0" encoding="UTF-8"?>
<launch>
  <include file="$(find robot)/world/turtlebot3_house.world">
  </include>
  <param name="robot_description" command="cat '$(find robot)/urdf/robot.xacro'"/>

  <arg name="x" default="0"/>
  <arg name="y" default="0"/>
  <arg name="z" default="0.5"/>

  <node name="robot_spawn" pkg="gazebo_ros" type="spawn_model" output="screen"
      args="-urdf -param robot_description -model robot -x $(arg x) -y $(arg y) -z $(arg z)" />

</launch>

my error

RLException: while processing /home/guru/first_robot/catkin_ws/src/robot/world/turtlebot3_house.world:
Invalid roslaunch XML syntax: no root <launch> tag
The traceback for the exception was written to the log file

the launch file which command which I used

roslaunch robot spawn.launch