Greetings! *** Nikolay Ivanov [2020-04-13 16:06]: >dt = datetime(1990, 1, 1, 0, 0, tzinfo=tzutc()) PyDERASN has never been aware of timezones in datetimes. It is just blind to them when encoding. However that is not explicitly mentioned in documentation and I will fix it. >ut == nut Indeed one of them contains original datetime object (with tzinfo set) and other is decoded one, without any timezone information. I think that the best thing to do is to explicitly .replace(tzinfo=None) for initialized datetimes in *Time objects. I will fix it (with documentation above) in the next release. Or maybe raise an error if someone uses timezone-away datetime objects, forcing him to make them neutral? What do you think? Anyway, if you want to use tzinfo-set objects, then you have to write your own wrappers. At least DER encoding works only with UTC time. -- Sergey Matveev (http://www.stargrave.org/) OpenPGP: CF60 E89A 5923 1E76 E263 6422 AE1A 8109 E498 57EF