New CancellationToken w/timeout

Timeout.cs

public static CancellationToken Timeout(this CancellationToken cancellationToken, TimeSpan timeout)
{
    if (!cancellationToken.CanBeCanceled)
        return new CancellationTokenSource(timeout).Token;

    var cancellationTokenSource = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
    cancellationTokenSource.CancelAfter(timeout);
    return cancellationTokenSource.Token;
}