def serialized(self):
        to_ret = {}
        for group, requirements in self.items():
            to_ret[group] = [str(requirement) for requirement in requirements]
        return to_ret
def __init__(self):
        self._ignore_sigint_lock = threading.Lock()
        self._threads_ignoring_sigint = 0
        self._ignoring_sigint_v2_engine = False