ERROR: Could not find a version that satisfies the requirement inst-api==0.3.0

[vol1ura]

I try to deploy my project onto Heroku , but am getting the following error upon running git push heroku master:

remote:        ERROR: Could not find a version that satisfies the requirement inst-api==0.3.0 (from -r /tmp/build_2960040d/requirements.txt (line 9)) (from versions: none)        
remote:        ERROR: No matching distribution found for inst-api==0.3.0 (from -r /tmp/build_2960040d/requirements.txt (line 9))        
remote:  !     Push rejected, failed to compile Python app. 

But locally all works fine, I use virtualenv and pip install -r requirements.txt process without problems on my PC.
Why it is not pushed on heroku?

[uriyyo]

Which version of python are you using?

The minimal version of python for inst-api is python 3.7

[vol1ura]

Oh, in my default heroku account was Python 3.6.12.
Specifying Python 3.8.7 solve this problem - https://devcenter.heroku.com/articles/python-support
To specify a Python runtime, it is needed to add runtime.txt file to app’s root directory that declares the exact version number to use:

$ cat runtime.txt
python-3.9.0 

Thank you for helpful answer!

[uriyyo]

Happy to hear that you solve this issue🙂