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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 retire_subjects(self, subjects, reason='other'):
 """ Retires subjects in this workflow. - **subjects** can be a list of :py:class:`Subject` instances, a list of subject IDs, a single :py:class:`Subject` instance, or a single subject ID. - **reason** gives the reason the :py:class:`Subject` has been retired. Defaults to **other**. Examples:: workflow.retire_subjects(1234) workflow.retire_subjects([1,2,3,4]) workflow.retire_subjects(Subject(1234)) workflow.retire_subjects([Subject(12), Subject(34)]) """


        subjects = [ s.id if isinstance(s, Subject) else s for s in subjects ]

        return Workflow.http_post(
            '{}/retired_subjects'.format(self.id),
            json={
                'subject_ids': subjects,
                'retirement_reason': reason
            }
        )