@property
def entity_zero_or_selectable(self):
    if (self.entity_zero is not None):
        return self.entity_zero
    elif self.actual_froms:
        return list(self.actual_froms)[0]
    else:
        return None
@property
def entity_zero_or_selectable(self):
    if (self.entity_zero is not None):
        return self.entity_zero
    elif self.actual_froms:
        return list(self.actual_froms)[0]
    else:
        return None