many-to-many configuration using Entity Framework Code First

BlogContext.cs

public class BlogContext : DbContext
    {
        public BlogContext()
        {
        }

        public DbSet<Post> Posts { get; set; }
        public DbSet<Tag> Tags { get; set; }
        
        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            modelBuilder.Entity<Post>()
                .HasMany(p => p.Tags)
                .WithMany(t => t.Posts)
                .Map(m =>
                    {
                        m.ToTable("TagPosts");
                        m.MapLeftKey("PostId");
                        m.MapRightKey("TagId");
                    });
        }
    }

Post.cs

public class Post
    {
        public Post()
        {
            this.Tags = new List<Tag>();            
        }
        public int Id { get; set; }

        [Required]
        [MaxLength(125)]
        public string Title { get; set; }

        [Required]
        public string Content { get; set; }

        public DateTime DateCreated { get; set; }

        public virtual ICollection<Tag> Tags { get; set; }        
    }

Tag.cs

public class Tag
    {
        public Tag()
        {
            this.Posts = new List<Post>();
        }
        public int Id { get; set; }

        [MaxLength(125)]
        public string TagText { get; set; } 
        public virtual ICollection<Post> Posts { get; set; }
    }