My current sketch draws a repeatedly growing and shrinking ellipse. Help me change the program so that this behavior is encapsulated inside a class. Move all this behavior to a class, then have mouse clicks create instances of the class on the screen. Use a JavaScript push() to store the instances of the class that you create, and update and display all of them in the draw() loop. 

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​

​

let x = 300;

let y = 300;

let d = 0;

let incr = 2;

let maxSize = 150;

​

function setup() {

  createCanvas(600, 600);

}

​

function draw() {

  background(150);

  ellipse(x, y, d, d);

  if (d > maxSize || d < 0) {

    incr = -incr;

  }

  d += incr;

}