I am trying to host the Django backend of my website on railway, however when I try and deploy the server, I get:

/bin/bash: line 1: gunicorn: command not found

error in logs

I've followed all the steps of creating a requirements.txt file, and a Procfile, but I still get the same error.

I did: pip freeze > requirements.txt, so that it contains gunicorn==23.0.0 and I also made a Procfile containing, web: gunicorn 'backend.wsgi (backend is the directory containing the wsgi file). also made a runtime.txt file with, Python 3.13.1 in it