def attempt(self, envelope, attempts):
        raise NotImplementedError()
:param bytes: A chunk of bytes to check.
dataset/ETHPy150Open slimta/python-slimta/slimta/relay/__init__.py/Relay.attempt--crossover with--dataset/ETHPy150Open kivy/kivy-ios/tools/external/binaryornot/helpers.py/is_binary_string