read me...............
requirments
1. install os module #pip install os
2. install flask frame work #pip install flask

first exicute the stage1,py  file by running the command "python stage1.py"
then run the stage2.py file using the same command by changing the argument
enter the port number in the cosole
open postman for viewing the requests as mentioned in the question
select the desired method and url in the postman
eg:post localhost:5000 index