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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, content):
 """Enumerates the bytes of the supplied bytearray and updates the CRC-64. No return value. """


        for byte in content:
            self._crc64 = (self._crc64 >> 8) ^ self._lookup_table[(self._crc64 & 0xff) ^ byte]