code: def __init__(self, ll, val, prv=None, nxt=None):
      self.ll = ll
      self.val = val
      self.prv = prv
      self.nxt = nxt
  
imports: import functools
  import inspect
  import itertools
  from operator import attrgetter
  from typing import Any
  from gluonts.pydantic import pydantic, deep_update
label_desc: Use image node_id 1 to create a new ListElement object  with example: obj = ListElement(ll, val, prv, nxt)