1classDiagram
2    Animal <|-- Duck
3    Animal <|-- Fish
4    Animal <|-- Zebra
5    Animal : +int age
6    Animal : +String gender
7    Animal: +isMammal()
8    Animal: +mate()
9    class Duck{
10        +String beakColor
11        +swim()
12        +quack()
13    }
14    class Fish{
15        -int sizeInFeet
16        -canEat()
17    }
18    class Zebra{
19        +bool is_wild
20        +run()
21    }