__init__.py 文件源码

def _check_mutually_exclusive_options(self):
        # auto_now, auto_now_add, and default are mutually exclusive
        # options. The use of more than one of these options together
        # will trigger an Error
        mutually_exclusive_options = [self.auto_now_add, self.auto_now,
                                      self.has_default()]
        enabled_options = [option not in (None, False)
                          for option in mutually_exclusive_options].count(True)
        if enabled_options > 1:
            return [
                checks.Error(
                    "The options auto_now, auto_now_add, and default "
                    "are mutually exclusive. Only one of these options "
                    "may be present.",
                    hint=None,
                    obj=self,
                    id='fields.E160',
                )
            ]
        else:
            return []