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: uuid_test.go
    path of file: ./repos/tank/code/tool/uuid
    
    the code of the file until where you have to start completion: // This package provides immutable UUID structs and the functions
// NewV3, NewV4, NewV5 and Parse() for generating versions 3, 4
// and 5 UUIDs as specified in RFC 4122.
//
// Copyright (C) 2011 by Krzysztof Kowalik <chris@nu7hat.ch>
package uuid

import (
	"regexp"
	"testing"
)

const format = "^[a-z0-9]{8}-[a-z0-9]{4}-[1-5][a-z0-9]{3}-[a-z0-9]{4}-[a-z0-9]{12}$"

func TestParse(t *testing.T) {
	_, err := Parse([]byte{1, 2, 3, 4, 5})
	if err == nil {
		t.Errorf("Expected error due to invalid UUID sequence")
	}
	base, _ := NewV4()
	u, err := Parse(base[:])
	if err != nil {
		t.Errorf("Expected to parse UUID sequence without problems")
		return
	}
	if u.String() != base.String() {
		t.Errorf("Expected parsed UUID to be the same as base, %s != %s", u.String(), base.String())
	}

    
func TestNewV3(t *testing.T) {
	u, err := NewV3(NamespaceURL, []byte("golang.org"))
	if err != nil {
		t.Errorf("Expected to generate UUID without problems, error thrown: %d", err.Error())
		return
	}
	if u.Version() != 3 {
		t.Errorf("Expected to generate UUIDv3, given %d", u.Version())
	}
	if u.Variant() != ReservedRFC4122 {
		t.Errorf("Expected to generate UUIDv3 RFC4122 variant, given %x", u.Variant())
	}
	re := regexp.MustCompile(format)
	if !re.MatchString(u.String()) {
		t.Errorf("Expected string representation to be valid, given %s", u.String())
	}
	u2, _ := NewV3(NamespaceURL, []byte("golang.org"))
	if u2.String() != u.String() {
		t.Errorf("Expected UUIDs generated of the same namespace and name to be the same")
	}
	u3, _ := NewV3(NamespaceDNS, []byte("golang.org"))
	if u3.String() == u.String() {
		t.Errorf("Expected UUIDs generated of different namespace and the same name to be different")
	}
	u4, _ := NewV3(NamespaceURL, []byte("code.google.com"))
	if u4.String() == u.String() {
		t.Errorf("Expected UUIDs generated of the same namespace and different names to be different")
	}
}