What does "XORed SHA256 digests of each of the identifiers" mean here?

[edent]

I'm trying to understand how my AP accounts can share a list of who follows them.

The documentation for Follower synchronization mechanism says:

digest = hexadecimal representation of the XORed SHA256 digests of each of the identifiers in the partial collection

The following code produces the correct output based on the documentation:

>>> import hashlib
>>> sha256_hash = hashlib.sha256("https://mastodon.social/users/Gargron".encode()).digest()
>>> sha256_hash.hex()
'b08ab6951c7d6cc2b91e17ebd9557da7fae02489728e9332fcb3a97748244d50

But there's no explanation or example of what it looks like for multiple followers.

I assume it should it be:

>>> import hashlib
>>> sha_1 = hashlib.sha256("https://mastodon.social/users/Gargron".encode()).digest()
>>> sha_2 = hashlib.sha256("https://mastodon.social/users/Edent".encode()).digest()
>>> xor_result = bytes(a ^ b for a, b in zip(sha_1, sha_2))
>>> xor_result.hex()
'f11cad446acb5adc7b125c686741840c177d3947308201e13e66671f841a1a2e

I think it could be helpful to have a bit more detail here. Perhaps giving an example that people can test against?

Also, should social.sitedethib.com be replaced with an example domain?

Re: mastodon/mastodon#14510