diff --git a/rustbyexample/0123/src/main.rs b/rustbyexample/0123/src/main.rs
index 4189fd5..5658d6c 100644
--- a/rustbyexample/0123/src/main.rs
+++ b/rustbyexample/0123/src/main.rs
@@ -23,6 +23,13 @@ struct Color {
     blue: u8,
 }
 
+impl Display for Color {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        write!(f, "RGB ({}, {}, {}) 0x{:02X}{:02X}{:02X}", self.red, self.green, self.blue, self.red, self.green, self.blue)
+    }
+}
+
+
 fn main() {
     for city in [
         City { name: "Dublin", lat: 53.347778, lon: -6.259722 },
@@ -38,5 +45,6 @@ fn main() {
         Color { red: 0, green: 0, blue: 0 },
     ].iter() {
         println!("{:?}", *color);
+        println!("{}", *color);
     }
 }