Does section 654, subdivision (a) of the California Criminal Code apply to punish an act or omission that is punishable by different provisions of the law in different ways?

Section 654, subdivision (a) provides that "An act or omission that is punishable in different ways by different provisions of law shall be punished under the provision that provides for the longest potential term of imprisonment, but in no case shall the act or omission be punished under more than one provision." The purpose of section 654 is "to insure that a defendant's punishment will be commensurate with his culpability." (People v. Perez (1979) 23 Cal.3d 545, 550-551.)