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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 get_customer_transitions(self, issue_id_or_key):
 """ Returns a list of transitions that customers can perform on the request :param issue_id_or_key: str :return: """

        url = 'rest/servicedeskapi/request/{}/transition'.format(issue_id_or_key)

        return self.get(url, headers=self.experimental_headers)