Does a jury need to be unanimous in finding that a defendant bears no burden to prove mitigating factors?

"The trial court was not required to instruct the jury that defendant bears no burden to prove mitigating factors or that it need not be unanimous in finding the existence of any mitigating factor." ( People v. Adams (2014) 60 Cal.4th 541, 580, 179 Cal.Rptr.3d 644, 336 P.3d 1223.) "Defendant was not entitled to an instruction that there is a presumption in favor of life without parole." ( People v. Boyce (2014) 59 Cal.4th 672, 724, 175 Cal.Rptr.3d 481, 330 P.3d 812.)