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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 create_milestones(self, project_id, milestones):
 """ With this function you can create multiple milestones in a single request. See the "create" function for a description of the individual fields in the milestone. """

        path = '/projects/%u/milestones/create' % project_id
        req = ET.Element('request')
        for milestone in milestones:
            req.append(self._create_milestone_elem(*milestone))
        return self._request(path, req)