What is a defendant's credit for time spent in custody under section 2900.5 of the California Criminal Code?

Section 2900.5, subdivision (a), provides in pertinent part: "In all felony . . . convictions, either by plea or by verdict, when the defendant has been in custody, including, but not limited to, any time spent in a jail, . . . [or] prison, . . . all days of custody of the defendant, . . . shall be credited upon his or her term of imprisonment . . . ." Section 2900.5, subdivision (d), provides in pertinent part: "It is the duty of the court imposing the sentence to determine . . . the total number of days to be credited pursuant to this section. The total number of days to be credited shall be contained in the abstract of judgment provided for in Section 1213." When a court pronounces a single aggregate term and imposes the combined sentence under sections 669 and 1170.1 and rule 4.452, it is the court's "duty as the new sentencing court to calculate and award all of defendant's credits, including those pertaining to the [prior] County case." (People v. Phoenix, supra, 231 Cal.App.4th at p. 1126, italics added.)