What is the test for imperfect self-defense?

"'Under the doctrine of imperfect self-defense, when the trier of fact finds that a defendant killed another person because the defendant actually, but unreasonably, believed he was in imminent danger of death or great bodily injury, the defendant is deemed to have acted without malice and thus can be convicted of no crime greater than voluntary manslaughter.' [Citations.]" (People v. Mejia-Lenares (2006) 135 Cal.App.4th 1437, 1446.)

The jury was instructed as to imperfect self-defense under CALCRIM No. 571: