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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 update(self, data):
 """Process more data."""

        self._md.update(data)
        bufpos = self._nbytes & 63
        self._nbytes += len(data)

        if self._rarbug and len(data) > 64:
            dpos = self.block_size - bufpos
            while dpos + self.block_size <= len(data):
                self._corrupt(data, dpos)
                dpos += self.block_size