Is a person who aids and abets a crime a principal in the crime?

13-15, citing People v. Prettyman, 14 Cal.4th 248, 259 (1996) (holding that under California law a person who aids and abets a crime is a principal in the crime, sharing the same guilt as the perpetrator, and that "[a]n aider and abettor is a person who, acting with (1) knowledge of the unlawful purpose of the perpetrator; and (2) the intent or purpose of committing, encouraging, or facilitating the commission of the offense, (3) by act or advice aids, promotes, encourages or instigates, the commission of the crime.") (internal quotation marks omitted).)