old_contents: let now;
  
  // Include a performance.now polyfill.
  // source https://github.com/tweenjs/tween.js/blob/master/src/Now.ts
  // In node.js, use process.hrtime.
  // eslint-disable-next-line
  // @ts-ignore
  if (typeof self === 'undefined' && typeof process !== 'undefined' && process.hrtime) {
    now = () => {
      // eslint-disable-next-line
  		// @ts-ignore
      const time = process.hrtime();
  
      // Convert [seconds, nanoseconds] to milliseconds.
      return time[0] * 1000 + time[1] / 1000000;
    };
  } else if (typeof self !== 'undefined' && self.performance !== undefined && self.performance.now !== undefined) {
    // In a browser, use self.performance.now if it is available.
    // This must be bound, because directly assigning this function
    // leads to an invocation exception in Chrome.
    now = self.performance.now.bind(self.performance);
  } else if (typeof Date !== 'undefined' && Date.now) {
    // Use Date.now if it is available.
    now = Date.now;
  } else {
    // Otherwise, use 'new Date().getTime()'.
    now = () => new Date().getTime();
  }
  
  export default now;
  
new_contents: // Include a performance.now polyfill.
  // source https://github.com/tweenjs/tween.js/blob/master/src/Now.ts
  let now;
  
  // In node.js, use process.hrtime.
  // eslint-disable-next-line
  // @ts-ignore
  if (typeof self === 'undefined' && typeof process !== 'undefined' && process.hrtime) {
    now = () => {
      // eslint-disable-next-line
  		// @ts-ignore
      const time = process.hrtime();
  
      // Convert [seconds, nanoseconds] to milliseconds.
      return time[0] * 1000 + time[1] / 1000000;
    };
  } else if (typeof self !== 'undefined' && self.performance !== undefined && self.performance.now !== undefined) {
    // In a browser, use self.performance.now if it is available.
    // This must be bound, because directly assigning this function
    // leads to an invocation exception in Chrome.
    now = self.performance.now.bind(self.performance);
  } else if (typeof Date !== 'undefined' && Date.now) {
    // Use Date.now if it is available.
    now = Date.now;
  } else {
    // Otherwise, use 'new Date().getTime()'.
    now = () => new Date().getTime();
  }
  
  export default now;
  
subject: Update now.js