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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 from_dict(self, d):
 """ Set this person from dict :param d: Dictionary representing a person ('sitting'[, 'id']) :type d: dict :rtype: Person :raises KeyError: 'sitting' not set """

        self.sitting = d['sitting']
        self.id = d.get('id', None)
        return self