Artemis shook his manacles. “Try it quickly.”
Holly did. The light winked green, and the cuffs popped open.
'Good. Excellent. Now let me do yours.“
Artemis's fingers paused over the keyboard.
'I don't read the fairy language or numerals.“
'You do. In fact, you are the only human who does,“ said Holly. ”You just don't remember.
The pad is standard layout. Zero to nine. Left to right.“
'Nine zero nine,“ muttered Artemis, pressing the appropriate keys. Holly's cuffs popped on the first try, which was fortunate because there would be no time for a second.

The Opal Deception, Chapter 7