A .mailmap file is used to map commit author info where committers use multiple names or email addresses to a single unique name/email. It is usually located in the root of a repo. See e.g. https://stackoverflow.com/questions/13777171/configuring-git-log-to-use-mailmap-by-default

I cannot find any mention of the feature in this repo; GitPyhon seems to ignore the file. It would be quite useful to allow using that file. Maybe replacing the author name and email in raw, or adding a second row-mailmapped column for example.