`hmac`

HMAC keyed-hash message authentication. Builds on hashlib.

Source-of-record: Lib/hmac.py, hmac docs.

API

Function / class	Purpose
`new(key, msg=None, digestmod)`	Construct HMAC.
`digest(key, msg, digest)`	One-shot.
`compare_digest(a, b)`	Constant-time compare.
`HMAC.update(msg)`	Feed bytes.
`HMAC.digest()` / `hexdigest()`	Finalise.
`HMAC.copy()`	Fork.
`HMAC.name`, `digest_size`, `block_size`	Metadata.

digestmod accepts a hashlib name, constructor, or hashlib.new-returned object.

Area	State
`HMAC`, `new`, `digest`	Complete.
`compare_digest`	Complete via `subtle.ConstantTimeCompare`.