The reason for deprecating Temporary is that the set of "temporary" errors
was extremely ill-defined. The initial issue for https://go.dev/issue/45729
discusses the de facto definition of Temporary and the confusion resulting
from it.
Perhaps there's a useful definition of temporary or retriabl
A multipart.Writer exists in one of three states currently:
1. CreatePart has not been called.
2. CreatePart has been called at least once, but Close has not been called
yet.
3. Close has been called.
This proposal would introduce a fourth state:
4. FlushLastPart has been called. CreatePart or
