Hello,
If you could please look at the submitting patch guidelines/howto in the following link:
https://www.openembedded.org/wiki/How_to_submit_a_patch_to_OpenEmbedded
At a very high level you should make local changes to the repo, commit them through git and create a patch from your commit that you can then send through git send-email.
That would allow us to get the patch in the required format (vs attachments), to be able to merge it in our repos.
I would also evaluate if python3-fmt belongs to the openembedded
core repo or the meta-python layer in the meta-openembedded repo (http://git.openembedded.org/meta-openembedded/tree/meta-python).
Cheers,
Alejandro
To allow python < 3.6 users to use python 3.6 style f-string formatting, fmt library needs to be integrated.