code: async def on_isupport_maxlist(self, value):
          
          self._list_limits = {}
  
          for entry in value.split(','):
              modes, limit = entry.split(':')
  
              # Assign limit to mode group and add lookup entry for mode.
              self._list_limits[frozenset(modes)] = int(limit)
              for mode in modes:
                  self._list_limit_groups[mode] = frozenset(modes)
docs: Limits on channel modes involving lists.