// Interface declaration
interface Animal 
{
  function speak(): String
  function move(): String
}
// Abstract class partially implementing Animal
abstract class Mammal implements Animal
{
  var name: String
 
  construct(nameInput: String) 
  {
    this.name = nameInput
  }
 
  // Abstract method - must be implemented by subclass
  abstract function speak(): String
 
  // Concrete method
  function move(): String 
  {
    return "${name} walks on land";
  }
}

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