What is the test for a jury to convict a defendant of murder in the first degree?

In People v. Lloyd, 98 Cal.App.2d 305, 311, 220 P.2d 10, 14, it was said: 'The facts established by the prosecution witnesses prove nothing short of murder in the first degree. Since appellant denied In toto such testimony, denied his presence on the premises of the deceased on the night of the murder, why should the court have confused the sole issue of murder in the first degree with instructions concerning, and definitions of, crimes included in the crime charged? In charging a jury, the court should be guided by the facts proved. When a person is accused of murder [9 Cal.3d 237] in the first degree, if the evidence is of such nature as to warrant a verdict for no lesser crime, if the defendant is guilty at all, the court should refuse to instruct as to crimes included within first degree murder.' (See also People v. Mabry, 71 Cal.2d 430, 437--438, 78 Cal.Rptr. 655, 455 P.2d 759.)