For the purposes of this chapter—
(2)
The term “United States” includes the several States, the District of Columbia, and the Commonwealth of Puerto Rico.
(3) The term “pre-Columbian monumental or architectural sculpture or mural” means—
(4)
The term “country of origin”, as applied to any pre-Columbian monumental or architectural sculpture or mural, means the country where such sculpture or mural was first discovered.