text: """Tornado handlers for the terminal emulator."""
  
  # Copyright (c) Jupyter Development Team.
  # Distributed under the terms of the Modified BSD License.
  
  import json
  from tornado import web
  import terminado
  from notebook._tz import utcnow
  from ..base.handlers import IPythonHandler
  from ..base.zmqhandlers import WebSocketMixin
  
  
  class TerminalHandler(IPythonHandler):
      """Render the terminal interface."""
      @web.authenticated
      def get(self, term_name):
          self.write(
              self.render_template(
                  'terminal.html',
                  ws_path=f"terminals/websocket/{term_name}",
              )
          )
  
  
  class NamedTerminalHandler(IPythonHandler):
      """Creates and renders a named terminal interface."""
      @web.authenticated
      def get(self):
          model = self.terminal_manager.create()
          term_name = model['name']
          new_path = self.request.path.replace("terminals/new", "terminals/" + term_name)
          self.redirect(new_path)
  
  
  class NewTerminalHandler(IPythonHandler):
      """Creates and renders a terminal interface using the named argument."""
      @web.authenticated
      def get(self, term_name):
          if term_name == 'new':
              raise web.HTTPError(400, "Terminal name 'new' is reserved.")
          new_path = self.request.path.replace(f"new/{term_name}", term_name)
          if term_name in self.terminal_manager.terminals:
              self.set_header('Location', new_path)
              self.set_status(302)
              self.finish(json.dumps(self.terminal_manager.get_terminal_model(term_name)))
              return
  
          self.terminal_manager.create_with_name(term_name)
          self.redirect(new_path)
  
  
  class TermSocket(WebSocketMixin, IPythonHandler, terminado.TermSocket):
  
      def origin_check(self):
          """Terminado adds redundant origin_check
  
          Tornado already calls check_origin, so don't do anything here.
          """
          return True
  
      def get(self, *args, **kwargs):
          if not self.get_current_user():
              raise web.HTTPError(403)
          if not args[0] in self.term_manager.terminals:
              raise web.HTTPError(404)
          return super().get(*args, **kwargs)
  
      def on_message(self, message):
          super().on_message(message)
          self._update_activity()
  
      def write_message(self, message, binary=False):
          super().write_message(message, binary=binary)
          self._update_activity()
  
      def _update_activity(self):
          self.application.settings['terminal_last_activity'] = utcnow()
          # terminal may not be around on deletion/cull
          if self.term_name in self.terminal_manager.terminals:
              self.terminal_manager.terminals[self.term_name].last_activity = utcnow()
  