If you have the test.py file in the corresponding folder in drive as in the below attached image, then the command which you use to run the test.py file is as mentioned below,
!python gdrive/My\ Drive/Colab\ Notebooks/object_detection_demo-master/test.py
Additional Info:
If you jusst want to run !python test.py then you should change directory, by the following command before it,
%cd gdrive/My\ Drive/Colab\ Notebooks/object_detection_demo-master/
