Exercise 3.1 Workcell XACRO

[Lingaprahasam]

roslaunch myworkcell_support urdf.launch

end up with error

#====================================================================#
Invalid tag: Cannot load command parameter [robot_description]: command [/opt/ros/kinetic/lib
/xacro/xacro --inorder '/home/lingaa/Training_ws/src/myworkcell_support/urdf/workcell.xacro'] returne
d with code [2].

Param xml is
The traceback for the exception was written to the log file
#====================================================================#

I really don't know how to solve this error. It seems everything right. But end up in error.