method Keyring.prototype.addFromMnemonicimport { Keyring } from "https://dotland.deno.dev/x/polkadot@0.2.38/keyring/mod.ts"; addFromMnemonic(mnemonic: string,meta?: KeyringPair$Meta,type?: KeypairType,): KeyringPairParametersmnemonic: stringoptionalmeta: KeyringPair$Meta = [UNSUPPORTED]optionaltype: KeypairType = [UNSUPPORTED]ReturnsKeyringPair