code: def value(self, new_value=None):
  		
  		if new_value is not None:
  			if self.__ro_flag:
  				raise RuntimeError('Read-only cookie changing attempt')
  			self.__value = new_value
  		return self.__value
docs: Return cookie value. Cookie value can be updated, when new_value is not None. Cookie value
  		couldn't be changed if cookie is in read-only mode (RuntimeError exception is raised).
  
  		:param new_value: new value to set
  		:return: str