SOURCE

function Person() {
  
}
Person.prototype.dance = function() {
  return "123"
}

function Ninja() {
  
}

Ninja.prototype = new Person()



function assert(value,text) {
  if(value === true) {
    console.log(text)
  } else {
    console.log('error')
  }
}


const ninja = new Ninja()
console.log(ninja.consutrctor ===  Person.prototypr)