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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 add_request_participants(self, issue_id_or_key, users_list):
 """ Add users as participants to an existing customer request The calling user must have permission to manage participants for this customer request :param issue_id_or_key: str :param users_list: list :return: """

        url = 'rest/servicedeskapi/request/{}/participant'.format(issue_id_or_key)
        data = {'usernames': users_list}

        return self.post(url, data=data)