return property attributes
        :param prop:
        :return:

def get_prop(self, prop, ef=None):
        """
        return property attributes
        :param prop:
        :return:
        """
        if ef:
            return self.ef[prop]
        else:
            if prop == 'auc':
                return self.auc
            elif prop == 'ensemble':
                return self.ensemble