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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 affiliation_history(self):
 """Unordered list of IDs of all affiliations the author was affiliated with acccording to Scopus. """

        affs = self._json.get('affiliation-history', {}).get('affiliation')
        try:
            return [d['@id'] for d in affs]
        except TypeError:  # No affiliation history
            return None