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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def write_error(self, status_code: int, **kwargs: Any) -> None: """Override to implement custom error pages. ``write_error`` may call `write`, `render`, `set_header`, etc to produce output as usual. If this error was caused by an uncaught exception (including HTTPError), an ``exc_info`` triple will be available as ``kwargs["exc_info"]``. Note that this exception may not be the "current" exception for purposes of methods like ``sys.exc_info()`` or ``traceback.format_exc``. """

        if self.settings.get("serve_traceback") and "exc_info" in kwargs:
            # in debug mode, try to send a traceback
            self.set_header("Content-Type", "text/plain")
            for line in traceback.format_exception(*kwargs["exc_info"]):
                self.write(line)
            self.finish()
        else:
            self.finish(
                "<html><title>%(code)d: %(message)s</title>"
                "<body>%(code)d: %(message)s</body></html>"
                % {"code": status_code, "message": self._reason}
            )