function extractAuthorimport { extractAuthor } from "https://dotland.deno.dev/x/polkadot@0.2.23/api-derive/type/util.ts"; extractAuthor(digest: Digest, sessionValidators?: AccountId[]): AccountId | undefinedParametersdigest: DigestoptionalsessionValidators: AccountId[] = [UNSUPPORTED]ReturnsAccountId | undefined