Display a standalone shell.

def display_console(self, request):
        """Display a standalone shell."""
        if 0 not in self.frames:
            if self.console_init_func is None:
                ns = {}
            else:
                ns = dict(self.console_init_func())
            ns.setdefault("app", self.app)
            self.frames[0] = _ConsoleFrame(ns)
        is_trusted = bool(self.check_pin_trust(request.environ))
        return Response(
            render_console_html(secret=self.secret, evalex_trusted=is_trusted),
            mimetype="text/html",
        )