def hook(self, hook_name):
        def wrapper(fn):
            self.register_hook(hook_name, fn)
            return fn
        return wrapper
Gets the naive datetime of the certificates 'not_after' field.
dataset/ETHPy150Open nickfrostatx/flask-hookserver/flask_hookserver.py/Hooks.hook--crossover with--dataset/ETHPy150Open Netflix/security_monkey/security_monkey/watchers/iam/iam_ssl.py/cert_get_not_after