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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 size_in_bytes(self, offset, timestamp, key, value, headers=None):
 """ Actual size of message to add """

        assert not headers, "Headers not supported in v0/v1"
        magic = self._magic
        return self.LOG_OVERHEAD + self.record_size(magic, key, value)