code: def set_default_headers(self) -> None:
      if streamlit.web.server.routes.allow_cross_origin_requests():
          self.set_header("Access-Control-Allow-Origin", "*")
  
file_path: streamlit/lib/streamlit/web/server/component_request_handler.py
imports: import mimetypes
  import os
  import tornado.web
  import streamlit.web.server.routes
  from streamlit.components.v1.components import ComponentRegistry
  from streamlit.logger import get_logger
label_desc: Use image node_id 4 for calling the ComponentRequestHandler obj's underlying member method code with example usage: obj.set_default_headers() without return types