def METHOD_NAME(fixtures_path, *extra_args):
    """
    Invokes the manager CLI via a subprocess.
    @param fixturesPath `str` The path to the test fixtues .py file.
    @param extra_args `List[str]` Additional args to pass to the CLI.
    @return `subprocess.CompletedProcess` The results of the invocation.
    """
    # We may well be running inside a venv interpreter, but without
    # the venv being active in the current environment. The effect
    # of this is that the python on $PATH may not be the one that is
    # correctly configured with the appropriate dependencies, so we
    # attempt to use the same executable as the tests.
    # Str wrapping prevents issues with Path objects in Windows
    # Python 3.7
    all_args = [sys.executable, "-m", "openassetio.test.manager"]
    if fixtures_path:
        all_args.extend(["-f", str(fixtures_path)])
    if extra_args:
        str_extra_args = [str(a) for a in extra_args]
        all_args.extend(str_extra_args)
    # We explicitly don't want an exception to be raised.
    # pylint: disable=subprocess-run-check
    return subprocess.run(all_args, capture_output=True)