Function to check if a string is an idna domain

[ITJamie]

It would be great if there a was a function in the library that would return true/false if the supplied string/bytes is an idn domain or not.

[elliotwutingfeng]

~How about this?~

def is_idna(s: str):
    return idna.encode(s).startswith(b'xn--')

~It works with both unicode and punycode formats.~ Do not use, will throw exception on unsuccessful encode().

[kjd]

I'm not sure if the above function would necessarily fit the bill, not all domains prefixed with xn-- are valid IDNs, only those that have a valid Punycode conversion based on the remainder of the string would be. @ITJamie can you confirm your request is to check for that it is a algorithmically valid IDN, or just has the potential to be a valid IDN based on further processing?

Also the above looks like it would throw an exception for an unsuccessful encode(), rather than returning False.

[kjd]

As there has been no further input from the requester in many months, closing this request.