Sections 2.500 to 2.630 shall be known as "the contracting and purchasing code." The term "this code" as used in Sections 2.500 to 2.630 shall mean the contracting and purchasing code, unless the context otherwise requires. The purpose of this code is to provide for the establishment of uniform, efficient and economical contracting and purchasing policies, procedures, rules and regulations for the City in accordance with the City Charter and Chapters 279A, 279B, and 279C of the Oregon Revised Statutes and are specifically adopted in place of the State Attorney General’s Model Rules.