Martin's original code (r32301) was pretty clear:

 32301     loewis         # IDNA allows decoding to operate on Unicode strings, too.
 32301     loewis         if isinstance(input, unicode):
 32301     loewis             labels = dots.split(input)
 32301     loewis         else:
 32301     loewis             # Must be ASCII string
 32301     loewis             unicode(input, "ascii")
 32301     loewis             labels = input.split(".")

but the py3k port, r55215, was clearly incomplete and the log message is explicit about it:


r55215 | guido.van.rossum | 2007-05-09 19:40:37 -0400 (Wed, 09 May 2007) | 3 lines

Random modifications that slightly improve the chances of this not blowing up.
Walter will fix it for real.

I hope I picked the right Walter for the "nosy" list.