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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 _reversebytes(self, start, end):
 """Reverse bytes in-place."""

        # Make the start occur on a byte boundary
        # TODO: We could be cleverer here to avoid changing the offset.
        newoffset = 8 - (start % 8)
        if newoffset == 8:
            newoffset = 0
        self._datastore = offsetcopy(self._datastore, newoffset)
        # Now just reverse the byte data
        toreverse = bytearray(self._datastore.getbyteslice((newoffset + start) // 8, (newoffset + end) // 8))
        toreverse.reverse()
        self._datastore.setbyteslice((newoffset + start) // 8, (newoffset + end) // 8, toreverse)