IDN explosion

mcasadevall@dawntreader:~/src$ cat ssl_test.py 
import socket
import ssl

hostname = 'räksmörgås.josefsson.org'
context = ssl.create_default_context()

with socket.create_connection((hostname, 443)) as sock:
    with context.wrap_socket(sock, server_hostname=hostname) as ssock:
        print(ssock.version())

mcasadevall@dawntreader:~/src$ python3 ssl_test.py 
Traceback (most recent call last):
  File "ssl_test.py", line 8, in <module>
    with context.wrap_socket(sock, server_hostname=hostname) as ssock:
  File "/usr/lib/python3.6/ssl.py", line 407, in wrap_socket
    _context=self, _session=session)
  File "/usr/lib/python3.6/ssl.py", line 814, in __init__
    self.do_handshake()
  File "/usr/lib/python3.6/ssl.py", line 1068, in do_handshake
    self._sslobj.do_handshake()
  File "/usr/lib/python3.6/ssl.py", line 694, in do_handshake
    match_hostname(self.getpeercert(), self.server_hostname)
  File "/usr/lib/python3.6/ssl.py", line 331, in match_hostname
    % (hostname, dnsnames[0]))
ssl.CertificateError: hostname 'räksmörgås.josefsson.org' doesn't match 'xn--rksmrgs-5wao1o.josefsson.org'