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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 perform_transition(self, issue_id_or_key, transition_id, comment=None):
 """ Perform a customer transition for a given request and transition ID. An optional comment can be included to provide a reason for the transition. :param issue_id_or_key: str :param transition_id: str :param comment: OPTIONAL: str :return: None """

        log.warning('Performing transition...')
        data = {'id': transition_id, 'additionalComment': {'body': comment}}
        url = 'rest/servicedeskapi/request/{}/transition'.format(issue_id_or_key)

        return self.post(url, headers=self.experimental_headers, data=data)