Run and Close a ros package inside python program

edit

Hello,

I have a python program that has a GUI.

I want when a user clicks on a button to execute a ROS package. Also, I have another button, when the user clicks, I want to close the running package.

I do not know how to do that.

I know how to open the program:

```

# calibration command
    calib_command_str = "rosrun camera_calibration cameracalibrator.py --size {}x{} {} {} --square {} right:={} left:={} left_camera:={} right_camera:={}".format(interior_corner_hor_axis, interior_corner_ver_axis, camera_service_check_value, approx_str, square_len, right_camera_image_topic, left_camera_image_topic, left_camera_image_super_topic, right_camera_image_super_topic)

    os.system(calib_command_str)

```

However, I do not how to close it.