In Serrato v. Superior Court (1978) 76 Cal.App.3d 459, the Court held that Penal Code section 859b establishes an absolute right for an in-custody felony defendant to have his preliminary hearing commenced within 10 court days after he has been arraigned or pleads to a criminal complaint, whichever first occurs, and that the 10-day period cannot be extended upon a "mere showing of good cause." ( Id., at p. 465.)