All acts done prior to March 9, 1937, in connection with the calling, giving notice, holding, or in anywise appertaining to a special election held in any city on the question of erecting, operating, and maintaining an electric light and power plant, site, buildings, and equipment thereof, for the purpose of furnishing electric energy for heat, light, and power for such city and its inhabitants and industries, and to pay for the cost thereof from the earnings thereof, if a majority of the voters voting at such election voted in favor of erecting, operating, and maintaining such a system, hereby are validated notwithstanding any defects, errors, or omissions in any of the acts done. Any such city hereby is authorized to erect, operate, and maintain an electric light and power plant, site, buildings, distribution system, and equipment thereof for the purpose of furnishing electric energy for heat, light, and power for the inhabitants and industries of such city.