[issue27321] Email parser creates a message object that can't be flattened

[Stéphane Wirtel]

Change by Stéphane Wirtel <stephane at wirtel.be>:


----------
versions: +Python 3.8 -Python 3.5

_______________________________________
Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue27321>
_______________________________________