public static Artist Generate(string name, Address address, string nickName = null)
 {
     return new Artist(name, address, nickName);
 }
 public static SoloArtist Generate(string name, Address address, string nickName = null, string instrument = "Guitar")
 {
     return new SoloArtist(address, name, nickName, instrument);
 }
 protected Artist(string name, Address address, string nickName = null)
 {
     Name = name;
     Address = address;
     SetNickName(nickName);
 }
 protected SoloArtist(Address address, string name, string nickname, string instrument) : base(name, address, nickname)
 {
     this.Instrument = instrument;
 }