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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 __add(self, val):
 """ Helper method for range addition. It is allowed to add only one compact subrange or ``range_t`` object at once. Parameters val : int or tuple or list or range Integer or range to add. Returns ------- __has : set ``self.__has`` extended by `val`. """


        if not isinstance(val, range_t):
            #sanitize it
            val = {self.__val_convert(val)} # convert to a set, coz I like it that way.

        else:
            val = val.toset()

        __has = deepcopy(self.__has) # simply add to a set.
        __has.update(val)

        return __has