def __init__(self, mode, target):
        if not is_exe_in_path('stunnel'):
            raise OSError('stunnel was not found in the exec path')

        if (STUNNEL_SERVER, STUNNEL_CLIENT) not in mode:
            raise AttributeError
        self.mode = mode
        self.target = target
        self.pid = None
dataset/ETHPy150Open reviewboard/reviewboard/reviewboard/scmtools/perforce.py/STunnelProxy.__init__/swapped operands of `not in`