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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, sequence):
 """Return concatenation of bitstrings joined by self. sequence -- A sequence of bitstrings. """

        s = self.__class__()
        i = iter(sequence)
        try:
            s._append(Bits(next(i)))
            while True:
                n = next(i)
                s._append(self)
                s._append(Bits(n))
        except StopIteration:
            pass
        return s