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I signed it!

CLAs look good, thanks!

Thanks for the PR, I’ll take a look this week

Thanks for fixing those warnings, this looks good.
For context, it's written the way it is because this is a direct translation of https://docs.python.org/2/library/difflib.html (section 7.4.5) to Fire.
I wonder if there's a way to push the changes upstream to the Python 2 documentation so we don't diverge from their example.

The context manager change lgtm.
For the open mode change, is there a way to do this without checking the version number with sys? E.g. does six have this mode? Or should we just use mode 'r' in all cases? I ask because putting the version check directly in the example sets us up for needing future changes later.

Thanks for the review.

I will open a PR for the Python documentation, good idea.
About the open mode, I would say we can go without any open mode as r is the default one. I am not aware a such a constant in six.

sgtm, let's remove the open mode.

I will open a PR for the Python documentation, good idea.

Great, thanks. cc me, or drop a link to the PR in this issue once it's open?

Sure :)

checking in on removing the open mode

Okay Sounds good

I aligned the script with the Python 3 version. WDYT?
You may have received notifications, but this is the BPO: https://bugs.python.org/issue34500.

lgtm,
will squash and merge this coming week.

All set, thanks!