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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 _corrupt(self, data, dpos):
 """Corruption from SHA1 core."""

        ws = list(self._BLK_BE.unpack_from(data, dpos))
        for t in range(16, 80):
            tmp = ws[(t - 3) & 15] ^ ws[(t - 8) & 15] ^ ws[(t - 14) & 15] ^ ws[(t - 16) & 15]
            ws[t & 15] = ((tmp << 1) | (tmp >> (32 - 1))) & 0xFFFFFFFF
        self._BLK_LE.pack_into(data, dpos, *ws)