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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 _extract_obo_synonyms(rawterm):
 """Extract the synonyms defined in the rawterm. """

        synonyms = set()
        # keys in rawterm that define a synonym
        keys = set(owl_synonyms).intersection(rawterm.keys())
        for k in keys:
            for s in rawterm[k]:
                synonyms.add(Synonym(s, owl_synonyms[k]))
        return synonyms