Choosing Your Testing Framework
Choose a testing framework, follow these steps:
Open the Settings/Preferences dialog, and under the node Tools, click the page Python Integrated Tools.
On this page, click the Default Test Runner field.
Choose the desired test runner:
Mind the following:
If a user already has the testing run/debug configuration for a specific file and for a specific testing framework, then PyCharm will launch this run/debug configuration, regardless of your chosen default test runner.
If the selected test runner is missing in the specified interpreter, the appropriate notification appears. Click the Fix button to download and install the corresponding framework.
With the test runner selected, PyCharm suggests the appropriate default run/debug configuration: