How to prevent unit testing from exiting when calling webbrowser.open()?

问题

I am developing unit test for code that use Google oauth2client.tools run_flow(). The problem is, this function will call Python webbrowser.open(), that will eventually (cmiiw), exit itself by calling sys.exit(). Therefore, even if I halt the code execution using threading.Event.wait(), it will eventually terminate, without continuing the rest of the unit testing code.

I have read this SO answer that previously was my problem, but now I still faced with this webbrowser.open() issue.

Any idea on how to solve this?

来源：https://stackoverflow.com/questions/31879381/how-to-prevent-unit-testing-from-exiting-when-calling-webbrowser-open