class_docstr: Vt100 input for Posix systems.
  (This uses a posix file descriptor that can be registered in the event loop.)
code: def raw_mode(self) -> ContextManager[None]:
      return raw_mode(self.stdin.fileno())
  
imports: from __future__ import annotations
  import sys
  import contextlib
  import io
  import termios
  import tty
  from asyncio import AbstractEventLoop, get_running_loop
  from typing import Callable, ContextManager, Generator, TextIO
  from ..key_binding import KeyPress
  from .base import Input
  from .posix_utils import PosixStdinReader
  from .vt100_parser import Vt100Parser
label_desc: Use image node_id 7 for calling the Vt100Input obj's underlying member method code with example usage: obj.raw_mode() and returns: raw_mode