The major changes from the previous version are:
- Add InitVar to specify initialize-only fields.
- Renamed __dataclass_post_init__() to __post_init().
- Rename cmp to compare.
- Added eq, separate from compare, so you can test
unorderable items for equality.
- Flushed out asdict() and astuple().
- Changed replace() to just call __init__(), and dropped
complex post-create logic.
Eric V. Smith
Mariatta
Barry Warsaw