class_docstr: A generic tree branch.
  
  Parameters
  ----------
  children
      Child branches and/or leaves.
class_docstr_tok: ["A","generic","tree","branch",".","Parameters","--","--","--","--","--","children","Child","branches","and\/or","leaves","."]
docstr: Move to the next node down the tree.
docstr_tok: ["Move","to","the","next","node","down","the","tree","."]
code: def next(self, x) -> Branch | Leaf:
      """Move to the next node down the tree."""
  
imports: from __future__ import annotations
  import abc
  import typing
  from collections import defaultdict
  from queue import Queue
  from xml.etree import ElementTree
  import pandas
  from river import base
label_desc: Use image node_id 2 for calling the Branch obj's underlying member method code with example usage: obj.next(x) without return types