Namedtuple
Quick way to create a class for example
from collections import namedtuple
ListNode = namedtuple("ListNode", ["val", "next"], defaults=[0, None])
node = ListNode()
print(node.val) # 0
print(node.next) # None
root = ListNode(4, node)
print(root.val) # 4
print(root.next) # node