If you have a Google account, you can save this code to your Google Drive.
Google will ask you to confirm Google Drive access.
Save file as:
If you have saved a file to Google Drive, you can open it here:
Click the button to see how many attributes the button element have.
The result should be 2 (the button element's id and onclick attributes).
Note: In Internet Explorer 8 and earlier, the attributes property will return a collection of all possible attributes for the element, and will, in this example, display a much higher number than 2.