class_docstr: Two dimensional buffer of :class:`.Char` instances.
docstr: For all the characters in the screen.
  Set the style string to the given `style_str`.
docstr_tok: ["For","all","the","characters","in","the","screen",".","Set","the","style","string","to","the","given","`","style_str","`","."]
code: def append_style_to_content(self, style_str: str) -> None:
      """
      For all the characters in the screen.
      Set the style string to the given `style_str`.
      """
      b = self.data_buffer
      char_cache = _CHAR_CACHE
  
      append_style = " " + style_str
  
      for y, row in b.items():
          for x, char in row.items():
              row[x] = char_cache[char.char, char.style + append_style]
  
imports: from __future__ import annotations
  from collections import defaultdict
  from typing import TYPE_CHECKING, Callable
  from prompt_toolkit.cache import FastDictCache
  from prompt_toolkit.data_structures import Point
  from prompt_toolkit.utils import get_cwidth
label_desc: Use image node_id 9 for calling the Screen obj's underlying member method code with example usage: obj.append_style_to_content(style_str) without return types