def size_in_bytes(self, offset, timestamp, key, value, headers):
        """ Return the expected size change on buffer (uncompressed) if we add
            this message. This will account for varint size changes and give a
            reliable size.
        """
 Return the expected size change on buffer (uncompressed) if we add
            this message. This will account for varint size changes and give a
            reliable size.
        
kafka/record/abc.py