code: def follower_ids(self, user):
          
          user = str(user)
          user = user.lstrip('@')
          url = 'https://api.twitter.com/1.1/followers/ids.json'
  
          if re.match(r'^\d+$', user):
              params = {'user_id': user, 'cursor': -1}
          else:
              params = {'screen_name': user, 'cursor': -1}
  
          while params['cursor'] != 0:
              try:
                  resp = self.get(url, params=params, allow_404=True)
              except requests.exceptions.HTTPError as e:
                  if e.response.status_code == 404:
                      log.info("no users matching %s", screen_name)
                  raise e
              user_ids = resp.json()
              for user_id in user_ids['ids']:
                  yield str_type(user_id)
              params['cursor'] = user_ids['next_cursor']
docs: Returns Twitter user id lists for the specified user's followers.
          A user can be a specific using their screen_name or user_id