In People v. Reed, 177 Ill. 2d 389, 394, 686 N.E.2d 584, 586, 226 Ill. Dec. 801 (1997) the supreme court held the language of section 5-8-1(c) is mandatory. The court also stated the following: "Requiring a written post sentencing motion will allow the trial court the opportunity to review a defendant's contention of sentencing error and save the delay and expense inherent in appeal if they are meritorious. Such a motion also focuses the attention of the trial court upon a defendant's alleged errors and gives the appellate court the benefit of the trial court's reasoned judgment on those issues. We therefore agree with the appellate court that the plain language now contained in section 5-8-1(c) shows a clear legislative intent to make a post sentencing motion the functional equivalent of a post trial motion for purposes of preserving issues for appeal." Reed, 177 Ill. 2d at 394, 686 N.E.2d at 586.