ruamel.yaml in python does that to a certain degree from what I've read, you might want to check it out if yaml is ok for your usecase! (
https://yaml.readthedocs.io/en/latest/)
I've given this some thought as well, and given that the eno libraries hold their own representation of data in memory this might actually be plausible to implement in some way. Still I fear this will turn out to be a hard, hard problem (as eno is not even generically serializable by design), so that's why I haven't explored it further. So for the moment I can only say - Maybe in the near future sometime, check back every once in a while! :)