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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_relation(cls, rawterm):
 """Extract the relationships defined in the rawterm. """

        relations = {}
        if 'subClassOf' in rawterm:
            relations[Relationship('is_a')] = l = []
            l.extend(map(cls._get_id_from_url, rawterm.pop('subClassOf')))
        return relations