code: def __contains__(self, item):
      try:
          wr = ref(item)
      except TypeError:
          return False
      return wr in self.data
  
imports: from _weakref import ref
  from types import GenericAlias
label_desc: Use image node_id 5 for calling the WeakSet obj's underlying member method code with example usage: obj.__contains__(item) and returns: unknown, False