code: def is_subscribed(self):
  		
  
  		subscribed = next(
  			(
  				config_item['value'] == 'true'
  				for config_item in self.config()
  				if config_item['key'] == 'isNautilusUser'
  			),
  			None
  		)
  
  		if subscribed:
  			self.tier = 'aa'
  		else:
  			self.tier = 'fr'
  
  		return subscribed
docs: The subscription status of the account linked to the :class:`MobileClient` instance.