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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_app_perms(self, *args):
 """ Get permissions related to the application specified in constructor Returns ------- set A set instance of `app_label.codename` formatted permission strings """

        if not hasattr(self, '_app_perms_cache'):
            self._app_perms_cache = get_app_perms(self.app_label)
        return self._app_perms_cache