 Complete the following phrase:  Diomidis Komninos is considered by many a heroic symbol of the Athens Polytechnic uprising. The student uprising is credited with helping trigger the eventual collapse of the military regime which ruled Greece since April 21, 1967. Nevertheless, the Polytechnic uprising was used as a pretext by junta hardliner Brigadier Dimitrios Ioannides to overthrow George Papadopoulos on November 25, 1973 and to put an end to a liberalisation process headed by Spiros Markezinis. The Ioannidis regime collapsed on July 1974 following the 