python - Code in context manager from one py test file affects another test file

Question

I have test_a.py and test_b.py files. In test_a.py file I have context manager with patch.dict like below:

with patch.dict("os.environ", {"AWS_REGION": "us-east-1"}):
    code...

In test_b.py file I have AWS_REGION = os.environ["AWS_REGION"] .

The problem: when I commented out the context manager in test_a.py file, the test_b.py file failed because os.environ doesn't have "AWS_REGION" .

My question:

1. Why are the two files interdependent?
2. Acknowledging that they're interdependent, why the patch.dict that only applies in the context manager will have an effect on test_b.py file?

question from:https://stackoverflow.com/questions/65943435/code-in-context-manager-from-one-py-test-file-affects-another-test-file

Answer 1

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