What are the implications of a plea bargain between a defendant and the prosecutor?

"The imposition of sentence and exercise of discretion are fundamentally and inherently judicial functions. [Citation.] While no bargain or agreement can divest the court of the sentencing discretion it inherently possesses [citations], a judge who has accepted a plea bargain is bound to impose a sentence within the limits of that bargain. [Citation.] 'A plea agreement is, in essence, a contract between the defendant and the prosecutor to which the court consents to be bound.' [Citations.] Should the court consider the plea bargain to be unacceptable, its remedy is to reject it, not to violate it, directly or indirectly. [Citation.] Once the court has accepted the terms of the negotiated plea, '[it] lacks jurisdiction to alter the terms of a plea bargain so that it becomes more favorable to a defendant unless, of course, the parties agree.' [Citation.]" (People v. Ames (1989) 213 Cal.App.3d 1214, 1217, 261 Cal.Rptr. 911.)