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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 serialize_to_txt(self):
 """ Serialize this subdomain record to a TXT record. The trailing newline will be omitted """

        txtrec = {
            'name': self.fqn if self.independent else self.subdomain,
            'txt': self.pack_subdomain()[1:]
        }
        return blockstack_zones.record_processors.process_txt([txtrec], '{txt}').strip()