Can't install project from pypi

[medatib531]

I want to install this project:

https://pypi.org/project/pynubls/

however when I do

$ pip install pynubls
Collecting pynubls
  Could not find a version that satisfies the requirement pynubls (from versions: )
No matching distribution found for pynubls

Can someone help?

I was on a Ubuntu VM.
Looks like the VM installation was somehow broken, I just made another VM and works fine now.
Thanks!