Is it possible to sync metric state this of type List[str]?

[bmosaicml]

I am trying to write a custom metric that maintains some state that is a List[str]. I want to be able to sync across ranks and concatenate the lists belonging to each rank. Reading through sync_dist it's unclear to me where such a synchronization would occur since by default function being applied is gather_all_tensors and there wouldn't be any tensors in the lists.

Is my understanding correct? Is there a different dist_sync_fn I could use to ensure correct syncing of non tensor lists?