Feature Request: Unloading function unload_dotenv()

Once load_dotenv() has run, variables are set. To remove them again for unit testing, I need a function, because tests should be independent. I coded this function already, but I think it would be nice to have it included in dotenv. I guess, I'm not the only one with the described problem. But maybe I'm wrong. I stepped over this more than once now. That's why I'm suggesting adding this function:

def unload_dotenv():
    """Remove all dotenv variables from environment."""

    dotenv_vars = set(dotenv_values().keys())
    for key in dotenv_vars:
        os.environ.pop(key, None)

Start by locating the existing load_dotenv() and dotenv_values() entry points and their tests. Check how dotenv-loaded variables are identified and verify that the proposed unload_dotenv() behavior is covered, including removing variables without affecting unrelated environment variables.