> 
> I feel I should have checked things with 'guix refresh -l' before
> submitting the patch, sorry about that.
> 
No worries, it's happened to me before as well on various ocassions  ;()

I would recommend working on something else until someone can upgrade python-dulwich properly or we figure out another approach.

Another option is to create your own Guix channel for these extra versions that you need.

If you do create your own Guix channel, feel free to join toys so that your channel is indexed there:

https://git.sr.ht/~whereiseveryone/toys#join

all the best,

jgart