I was trying to deploy a Django app in the Heroku following the official instruction. The project structure is as following,

It's good to mention that, I can run heroku locally from the src folder, heroku local web. Also the app create works fine, heroku create. While I tried to deploy the app using the command git push heroku master,

I get the error message in the terminal,

remote: -----> Failed to detect app matching https://codon-buildpacks.s3.amazonaws.com/buildpacks/heroku/python.tgz buildpack
remote:        More info: https://devcenter.heroku.com/articles/buildpacks#detection-failure
remote: 
remote:  !     Push failed
remote: Verifying deploy...
remote: 
remote: !   Push rejected to sheltered-sea-46201.
remote: 
To https://git.heroku.com/sheltered-sea-46201.git
 ! [remote rejected] master -> master (pre-receive hook declined)
error: failed to push some refs to 'https://git.heroku.com/sheltered-sea-46201.git'

I see the similar question in the SOF, but, none of them seems any help. For example, I shifted the requirements.txt file inside the src folder suggested in an answer and pip freeze again which is ineffective. What should I need to do to resolve the issue?

NOTE:

As someone suggested to use heroku buildpacks:set heroku/python,I tried and get the message,