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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 synonyms(self):
 """A ranked list of all the names associated with this Compound. Requires an extra request. Result is cached. """

        if self.cid:
            results = get_json(self.cid, operation='synonyms')
            return results['InformationList']['Information'][0]['Synonym'] if results else []