Starting January of next year, Mayor Bill de Blasio’s new municipal identification cards will not only help undocumented immigrants sign leases and meet photo ID requirements, but the cards will also be golden tickets into many of the city’s finest cultural institutions. 33 institutions belonging to the CIG (Cultural Institutions Group) will honor the Municipal ID as a one-year membership with benefits ranging from free admission to museum shop discounts. The 33 CIG members —all private nonprofit institutions on city property — include the Museum of Natural History, the New York Botanical Garden, the Brooklyn Academy of Music and the Metropolitan Museum of Art, among others.