The phrase school district, as used in section 10-711, is hereby declared to mean the school district as it existed immediately prior to and at the time of the issuance of any bonds by said school district, including all lands, property and inhabitants contained in said school district at the time of the issuance of any bonds, and all portions of said district subsequently separated from said district, whether by the formation of a new district or by any change of boundaries of the original district.