Can't launch turtlebot_gazebo example, kobuki_description not found.

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Background : Ubuntu 14.04, ROS indigo, gazebo 2.

I want to launch the example in turtlebot_gazebo:

roslaunch turtlebot_gazebo turtlebot_world.launch

The following error appears:

... logging to /home/osboxes/.ros/log/8aed81da-765e-11e6-b998-000c29a1f7dd/roslaunch-monmon-6172.log
Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

Traceback (most recent call last):
  File "/opt/ros/indigo/share/xacro/xacro.py", line 62, in <module>
    xacro.main()
  File "/opt/ros/indigo/lib/python2.7/dist-packages/xacro/__init__.py", line 687, in main
    process_includes(doc, os.path.dirname(args[0]))
  File "/opt/ros/indigo/lib/python2.7/dist-packages/xacro/__init__.py", line 246, in process_includes
    filename_spec = eval_text(elt.getAttribute('filename'), {})
  File "/opt/ros/indigo/lib/python2.7/dist-packages/xacro/__init__.py", line 485, in eval_text
    results.append(handle_extension(lex.next()[1][2:-1]))
  File "/opt/ros/indigo/lib/python2.7/dist-packages/xacro/__init__.py", line 473, in handle_extension
    return eval_extension("$(%s)" % s)
  File "/opt/ros/indigo/lib/python2.7/dist-packages/xacro/__init__.py", line 66, in eval_extension
    return substitution_args.resolve_args(str, context=substitution_args_context, resolve_anon=False)
  File "/opt/ros/indigo/lib/python2.7/dist-packages/roslaunch/substitution_args.py", line 312, in resolve_args
    resolved = _resolve_args(resolved, context, resolve_anon, commands)
  File "/opt/ros/indigo/lib/python2.7/dist-packages/roslaunch/substitution_args.py", line 325, in _resolve_args
    resolved = commands[command](resolved, a, args, context)
  File "/opt/ros/indigo/lib/python2.7/dist-packages/roslaunch/substitution_args.py", line 153, in _find
    pkg_path = rp.get_path(args[0])
  File "/usr/lib/python2.7/dist-packages/rospkg/rospack.py", line 200, in get_path
    raise ResourceNotFound(name, ros_paths=self._ros_paths)
rospkg.common.ResourceNotFound: kobuki_description
ROS path [0]=/opt/ros/indigo/share/ros
ROS path [1]=/opt/ros/indigo/share
ROS path [2]=/opt/ros/indigo/stacks
while processing /opt/ros/indigo/share/turtlebot_gazebo/launch/includes/kobuki.launch.xml:
Invalid <param> tag: Cannot load command parameter [robot_description]: command [/opt/ros/indigo/share/xacro/xacro.py '/opt/ros/indigo/share/turtlebot_description/robots/kobuki_hexagons_asus_xtion_pro.urdf.xacro'] returned with code [1]. 

Param xml is <param command="$(arg urdf_file)" name="robot_description"/>
The traceback for the exception was written to the log file

I think the important thing is rospkg.common.ResourceNotFound: kobuki_description

Please help to solve

And YES, I have tried searching before asking such as: this1 this2 this3 But they don't really give solution/fix the problem for me

Any help will be appreciated