The term “elementary school district” as used in Section 41050, Sections 41330 to 41343, inclusive, and Sections 41600 to 41972, inclusive, Sections 46304 and 46305, whichever are in effect, means, unless expressly provided otherwise, each elementary school district which is composed of a single elementary school district and each union elementary school district, joint union elementary school district, or unified school district; and does not include any elementary school district included within a union elementary school district or a joint union elementary school district or a unified school district.