What is the test for a motion to reduce a sentence under Rule 35(b)?

This court reviews a denial of a Rule 35(b) motion for abuse of discretion, United States v. Thayer, 857 F.2d 1358, 1359 (9th Cir.1988), or an abdication of discretion, United States v. Barker, 771 F.2d 1362, 1365 (9th Cir.1985). "The function of Rule 35(b) is 'simply to allow the district court to decide if, on further reflection, the original sentence now seems unduly harsh.' " United States v. Smith, 650 F.2d 206, 208 (9th Cir.1981) (quoting United States v. Maynard, 485 F.2d 247, 248 (9th Cir.1973)). A motion to reduce sentence under Rule 35(b) is therefore essentially a plea for leniency. Thayer, 857 F.2d at 1360; United States v. Hooton, 693 F.2d 857, 859 (9th Cir.1982).