Draw circle with UKit in Xcode playground

drawCircle.swift

//: Playground - noun: a place where people can play
import UIKit
import PlaygroundSupport

func drawCircle(x: CGFloat, y: CGFloat) {
    let p = UIBezierPath(ovalIn: CGRect(x: x, y: y, width: 10, height: 10))
    UIColor.blue.setFill()
    p.fill()
}

UIGraphicsBeginImageContextWithOptions(CGSize(width: 200, height: 200), false, 0)

// Draw circle
for i in stride(from: 0, to: 200, by: 10)  {
    drawCircle(x: CGFloat(i), y: CGFloat(i))
}

let im = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()

let containerView = UIView(frame: CGRect(x: 0.0, y: 0.0, width: 200.0, height: 200.0))
containerView.addSubview(UIImageView(image: im))
PlaygroundPage.current.liveView = containerView