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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 _slice(self, start, end):
 """Used internally to get a slice, without error checking."""

        if end == start:
            return self.__class__()
        offset = self._offset
        startbyte, newoffset = divmod(start + offset, 8)
        endbyte = (end + offset - 1) // 8
        bs = self.__class__()
        bs._setbytes_unsafe(self._datastore.getbyteslice(startbyte, endbyte + 1), end - start, newoffset)
        return bs