When the cause alleged for not pronouncing sentence is insanity, the court, if there is reasonable ground to believe that the defendant is insane, shall postpone the pronouncement of judgment and shall proceed to have the defendant’s mental condition determined in the manner prescribed in this title, so far as applicable, for the determination of the mental condition of a defendant before or during trial. Whenever it is determined that the defendant is or has become sane, the defendant must be brought before the court for judgment.