Rviz robot model will not open via script

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Without bash and python script: master and rviz works successfully

When I run "roscore" in first terminal. Master runs successfully

process[master]: started with pid [4355] ROS_MASTER_URI=http://userid:11311/

New terminal I type in "roslaunch /home/userid/catkin_ws/src/robot/launch/robot.launch". This basically open RVIZ with the robot model in grid successfully

Above steps are implemented as follows in bash and python script and it does NOT work.

##bashscript.sh

   source ~/.bashrc

 python pythonscript.py

##pythonscript.py

def init():
    os.system("gnome-terminal -e 'bash -c \"pwd; roslaunch /home/userid/catkin_ws/src/robot/launch/robot.launch; exec bash\"'")

if (__name__ == '__main__'):
    init()

This fails. RVIZ opens with a white blob in center on grid NOT the robot model. and left hand panel it says robot model error. status error.

Why rviz wouldn't work with script?