def get_fd(self):
        return self._fd
this assumes no exog, todo
dataset/ETHPy150Open seb-m/pyinotify/python2/pyinotify.py/WatchManager.get_fd--crossover with--dataset/ETHPy150Open statsmodels/statsmodels/statsmodels/tsa/varma_process.py/VarmaPoly.reduceform