In the Python world, tox (documentation) is a powerful testing tool that allows a project to test against many combinations of versioned environments. The django-coverage-plugin package (Github) uses tox to test against a matrix of Python versions (2.7, 3.4, 3.5, and 3.6) and Django versions (1.8, 1.9, 1.10, 1.11, 1.11tip, 2.0, 2.0tip), resulting in 25 valid combinations to test.
Preparing Your System Environments
tox needs to run from a virtual environment where it is installed and from which it’s run. As of Feb 2018, I would recommend a Python 2.7 environment so that you can use the detox package (see below) to parallelize your build’s workload. Installation of tox is usually into your base development environment and tox is usually included in your project’s requirements.txt file:
tox >= 1.8 detox
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