the first matches the value against 'BLACK' and the second succeeds and
binds the value to 'BLACK'.
Replacing 'BLACK' with '_':
I'd expect something similar, except for the binding part.
I think the same could be said for:
The PEP authors discussed this last night and (with a simple majority) we agreed that this restriction isn't all that important, so we're dropping it.
(We're considering other feedback carefully, but most of it require more deliberation.)