zoo.go

type Spider struct {}

func (s Spider) NumberOfLegs() int {
  return 8
}
func (s Spider) Genus() {
  return “Latrodectus” //strictly speaking, the genus of Black Widow spider
} 

type Dog struct {}
func (d Dog) NumberOfLegs() int {
  return 4
}
func (d Dog) Genus() {
  return “Canin”
}

type Stool struct {}
  func (s Stool) NumberOfLegs() int {
  return 3
}