You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: signed_data_test.go
    path of file: ./repos/go-ethereum/signer/core
    
    the code of the file until where you have to start completion: // Copyright 2019 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Fre
    
func TestComplexTypedData(t *testing.T) {
	t.Parallel()
	var td apitypes.TypedData
	err := json.Unmarshal([]byte(complexTypedData), &td)
	if err != nil {
		t.Fatalf("unmarshalling failed '%v'", err)
	}
	_, sighash, err := sign(td)
	if err != nil {
		t.Fatal(err)
	}
	expSigHash := common.FromHex("0x42b1aca82bb6900ff75e90a136de550a58f1a220a071704088eabd5e6ce20446")
	if !bytes.Equal(expSigHash, sighash) {
		t.Fatalf("Error, got %x, wanted %x", sighash, expSigHash)
	}
}