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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 _setsie(self, i):
 """Initialise bitstring with signed interleaved exponential-Golomb code for integer i."""

        if not i:
            self._setbin_unsafe('1')
        else:
            self._setuie(abs(i))
            self._append(Bits([i < 0]))