Why does persistent_cache add an underscore to the path if it's an imported function?

[Lucas-vdr-Horst]

When defining a function with persistent-cache in notebook A:

@mo.persistent_cache
def func(x):
    return x * 2

And importing it in notebook B:

from A import func

Calling func in notebook A creates a cache with a path like:
__marimo__/cache/func/D_<some hash>.pickle
But calling it in notebook B creates a cache with a path like:
__marimo__/cache/func_/D_<same hash>.pickle
Notice the added underscore at func_. Which results in the two notebooks not using the same cache.
Why is this?
I can't find it in the documentation, nor easily in the code.

Expected behavior: Both having the same path.

[dmadisetti]

I think we just never added test coverage for it, or thought about it- so it slipped through the cracks. Definitely a bug. Fixed in #6731

Thanks for reporting! Issues are a bit easier to track, but still appreciate you taking the time

[Lucas-vdr-Horst]

Thank you!