How to use the @nimiq/core.Wallet function in @nimiq/core

importWalletFromHexKey(key) {
		let privateKey = Nimiq.PrivateKey.unserialize(Nimiq.BufferUtils.fromHex(key.replace("0x", "")));
		let keypair = Nimiq.KeyPair.derive(privateKey);
		return new Nimiq.Wallet(keypair);
	}

} else {
			mnemonic = words;
		}

		if (mnemonic == null) {
			this.theWrapper.callbacks.error("AccountHelper:importWalletFromMnemonic", NimiqWrapper.ERROR_MESSAGES.BAD_PARAM_TYPE);
		} else {
			let entropy = null;
			if (Nimiq.MnemonicUtils.getMnemonicType(mnemonic) == Nimiq.MnemonicUtils.MnemonicType.LEGACY) {
				entropy = Nimiq.MnemonicUtils.legacyMnemonicToEntropy(mnemonic);
			} else {
				entropy = Nimiq.MnemonicUtils.mnemonicToEntropy(mnemonic);
			}

			let keypair = Nimiq.KeyPair.derive(entropy);
			return new Nimiq.Wallet(keypair);
		}
	}