This folder contains various tests. They are run by running 'tox' in the main folder of the project, where tox.ini is located. 'tox' is installed with 'pip install tox'. If you have issues running the tests with errors such 'You are using pip version 8.1.1, however version 19.2.1 is available.', please consider upgrading virtualenv with 'pip install virtualenv --upgrade'. Simply upgrading pip in this case does not work.