code: def transitions(self, issue, id=None, expand=None):
          
          params = {}
          if id is not None:
              params['transitionId'] = id
          if expand is not None:
              params['expand'] = expand
          return self._get_json('issue/' + str(issue) + '/transitions', params=params)['transitions']
docs: Get a list of the transitions available on the specified issue to the current user.
  
          :param issue: ID or key of the issue to get the transitions from
          :param id: if present, get only the transition matching this ID
          :param expand: extra information to fetch inside each transition