Scientific Computing with Python Projects - Arithmetic Formatter

Tell us what’s happening:
As far as I can tell this has nothing to do with my code. I opened the link, didn’t change anything and still got this message even on another computer:

python main.py
Traceback (most recent call last):
File “main.py”, line 2, in
from pytest import main
ModuleNotFoundError: No module named ‘pytest’
exit status 1

How do I fix this?

Your code so far
This does not involve my code.

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Challenge: Scientific Computing with Python Projects - Arithmetic Formatter

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