class_docstr: Interface for sending data to a session's client.
docstr: Deliver a ForwardMsg to the client.
  
  If the SessionClient has been disconnected, it should raise a
  SessionClientDisconnectedError.
code: def write_forward_msg(self, msg: ForwardMsg) -> None:
      """Deliver a ForwardMsg to the client.
  
      If the SessionClient has been disconnected, it should raise a
      SessionClientDisconnectedError.
      """
      raise NotImplementedError
  
imports: from abc import abstractmethod
  from dataclasses import dataclass
  from typing import Callable, Dict, List, Optional, cast
  from typing_extensions import Protocol
  from streamlit.proto.ForwardMsg_pb2 import ForwardMsg
  from streamlit.runtime.app_session import AppSession
  from streamlit.runtime.script_data import ScriptData
  from streamlit.runtime.scriptrunner.script_cache import ScriptCache
  from streamlit.runtime.uploaded_file_manager import UploadedFileManager
label_desc: Use image node_id 1 for calling the SessionClient obj's underlying member method code with example usage: obj.write_forward_msg(msg) without return types