hey @yingliu
Thank you for your response.
I am using a vendor product and deepstream 6.0.1 came preinstalled.
i did checkout the v1.1.1 tag and tried to run with
python3 deepstream_test_1.py …/…/…/…/samples/streams/sample_720p.h264
also had to install pyds from here DeepStream SDK FAQ - #22 by mchi
And it worked!
Thank you for the support.