def clean_semver(cls, version_spec):
        return re.sub(r"([<>=~])\s+?v?", "\\1", version_spec, re.IGNORECASE)
def __init__(self):
        self._ignore_sigint_lock = threading.Lock()
        self._threads_ignoring_sigint = 0
        self._ignoring_sigint_v2_engine = False