text: const { createCanvas, writeImage } = require('./index');
  const Vex = require('vexflow');
  
  const canvas = createCanvas();
  
  const VF = Vex.Flow;
  const renderer = new VF.Renderer(canvas, VF.Renderer.Backends.CANVAS);
  renderer.resize(500, 500);
  
  const context = renderer.getContext();
  context.save();
  context.fillStyle = 'white';
  context.fillRect(0, 0, 500, 500);
  context.restore();
  
  const stave = new VF.Stave(10, 50, 400);
  stave.addClef('treble').addTimeSignature('3/4');
  stave.setText('VexFlow on Node.js', VF.StaveModifier.Position.ABOVE);
  stave.setContext(context).draw();
  
  writeImage(canvas, 'sample.png');
  