Does the court have an obligation to instruct the jury on "mistake of law"?

Mendiburu argues the court sua sponte should have also (or perhaps alternatively) instructed the jury on "mistake of law" based on the same factual basis in the record. It is oft stated that mistakes as to the law are " 'almost never a defense.' [Citation.] There are rare instances where ignorance that a penal law prohibits one's conduct does provide a defense. Those instances include crimes punishing the failure to act (rather than an affirmative act) and certain conspiracies." (People v. Meneses (2008) 165 Cal.App.4th 1648, 1663.) Mendiburu cites nothing to suggest a "mistake of law" defense is even available to any of the charged offenses, much less that mistake of law is a "general principle[] of law that [is] commonly or closely and openly connected to the facts before the court and that [is] necessary for the jury's understanding of the case" that it gave rise here to a sua sponte instructional obligation. (People v. Montoya (1994) 7 Cal.4th 1027,

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