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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 crc(self):
 """ A checksum for the current visual object and its parent mesh. Returns crc: int, checksum of data in visual object and its parent mesh """

        # will make sure everything has been transferred
        # to datastore that needs to be before returning crc

        result = self._data.fast_hash()
        if hasattr(self.mesh, 'crc'):
            # bitwise xor combines hashes better than a sum
            result ^= self.mesh.crc()
        return result