Message 156699 - Python tracker

I want to update or create a comment to zip file.

For instance, I have test.zip file.
I'm using these statement to create a comment :

from zipfile import ZipFile

z=ZipFile('test.zip','a')
z.comment='Create a new comment'
z.close()

After to ran this script, the zip file test.zip doesn't including the new comment !

I can have the expected behavior when I add a new file inner zip archive.