How should I seed data to many to many relation in Entity Framework Code first 5.0

Just create a few movies and a few types and create relationships by adding some of those types to the Movie.Types collection (or the other way around), for example:

protected override void Seed(MyContext context)
{
    var movie1 = new Movie { Name = "A", Types = new List<Type>() };
    var movie2 = new Movie { Name = "B", Types = new List<Type>() };
    var movie3 = new Movie { Name = "C", Types = new List<Type>() };

    var type1 = new Type { MovieType = "X" };
    var type2 = new Type { MovieType = "Y" };

    movie1.Types.Add(type1);

    movie2.Types.Add(type1);
    movie2.Types.Add(type2);

    movie3.Types.Add(type2);

    context.Movies.Add(movie1);
    context.Movies.Add(movie2);
    context.Movies.Add(movie3);
}