How can I update my app because it has developed on Python2.7 from last 5 years, and python 3 does not support some old programming concept?
WARNING: Python 2.7 is no longer supported by the Python community as of 27 June, 2023. Python 2.7 will be end of support on 2024-01-30. As of 2024-01-30 you will no longer be able to deploy your App Engine Standard using python27. We recommend you to upgrade to the latest version of Python as soon as possible.
May I stop my application next 1 year to update it?
I have used wepapp2 and other library. I have to develop the whole project
It is not possible dear
Yes, you are correct. It may not support old programming concepts. But you can check with this Documentation which explains clearly about code changes required while migrating from python 2.7 to 3.x.
No, it is not required to stop the application. You can check with this Documentation for migrating 2.7 to 3.x. And also have a look at this Documentation for Runtime lifecycle.
Note: You must choose a more up-to-date runtime to deploy your application.