@property
    def _session(self):
        """Session to be used to send requests."""
        # We create and store a session into self under key '_session'. In this
        # way, we can check whether the session already exists and if so, we
        # may directly return it without re-creating it.
        if self.__dict__ not in '_session':
            self.__dict__['_session'] = self._start_new_session()

        return self.__dict__['_session']
dataset/ETHPy150Open s3rvac/retdec-python/retdec/conn.py/APIConnection._session/swapped operands of `not in`