Having worked with thousands of Chicago students, BLUE1647 is teaching a host of technology skills in web, mobile and game development.

One woman who had worked with thousands of young players over a 20-year period said the policy, in any case, was unenforceable.

It appears to have worked with thousands of revellers arriving, some coming from as far afield as Sweden, India, New York and Korea to celebrate.

However, having worked with thousands of businesspeople from interns to CEOs, Ledden says that she had not yet met a single person who does this.