class_docstr: The layout for a prompt_toolkit
  :class:`~prompt_toolkit.application.Application`.
  This also keeps track of which user control is focused.
  
  :param container: The "root" container for the layout.
  :param focused_element: element to be focused initially. (Can be anything
      the `focus` function accepts.)
class_docstr_tok: ["The","layout","for","a","prompt_toolkit",":","class",":","`","~prompt_toolkit.application.Application","`",".","This","also","keeps","track","of","which","user","control","is","focused",".",":","param","container",":","The","``","root","''","container","for","the","layout",".",":","param","focused_element",":","element","to","be","focused","initially",".","(","Can","be","anything","the","`","focus","`","function","accepts",".",")"]
docstr: Walk through all the layout nodes (and their children) and yield them.
docstr_tok: ["Walk","through","all","the","layout","nodes","(","and","their","children",")","and","yield","them","."]
code: def walk(self) -> Iterable[Container]:
      """
      Walk through all the layout nodes (and their children) and yield them.
      """
      yield from walk(self.container)
  
imports: from __future__ import annotations
  from typing import Generator, Iterable, Union
  from prompt_toolkit.buffer import Buffer
  from .containers import AnyContainer, ConditionalContainer, Container, Window, to_container
  from .controls import BufferControl, SearchBufferControl, UIControl
label_desc: Use image node_id 22 for calling the Layout obj's underlying member method code with example usage: obj.walk() without return types