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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 join(self, a, *args):
 """ Join given arguments into the same set. Accepts one or more arguments. """

        mapping = self._mapping
        set_a = mapping.setdefault(a, [a])

        for arg in args:
            set_b = mapping.get(arg)
            if set_b is None:
                set_a.append(arg)
                mapping[arg] = set_a
            elif set_b is not set_a:
                if len(set_b) > len(set_a):
                    set_a, set_b = set_b, set_a
                set_a.extend(set_b)
                for elem in set_b:
                    mapping[elem] = set_a