def update_or_create(self, **kwargs):
        return self.session().update_or_create(self.model, **kwargs)
append with value checking
dataset/ETHPy150Open lsbardel/python-stdnet/stdnet/odm/session.py/Manager.update_or_create--crossover with--dataset/ETHPy150Open correl/Transmission-XBMC/resources/lib/basictypes/rlist.py/rlist.append