code: def get_sea_permissions(calendar_id):
      
      return _process_get_perm_resp(
          get_permissions_url,
          post_sea_resource(get_permissions_url,
                            _create_get_perm_body(calendar_id)),
          TrumbaCalendar.SEA_CAMPUS_CODE,
          calendar_id)
docs: Return a list of Permission objects representing
      the user permissions of a given Seattle calendar.
      :return: a list sorted of trumba.Permission objects
               corresponding to the given campus calendar.
               None if error, [] if not exists
      raise DataFailureException or a corresponding TrumbaException
      if the request failed or an error code has been returned.