Post-punk:

Weeks after ending the Sex Pistols, Lydon formed the experimental group Public Image Ltd and declared the project to be "anti music of any kind". Public Image and other acts such as the Pop Group and the Slits had begun experimenting with dance music, dub production techniques and the avant-garde, while punk-indebted Manchester acts such as Joy Division, The Fall and A Certain Ratio developed unique styles which drew on a similarly disparate range of influences across music and modernist literature. Bands such as Scritti Politti, Gang of Four and This Heat incorporated Leftist political philosophy and their own art school studies in their work.

Please answer a question about this article. If the question is unanswerable, say "unanswerable". Which groups ignored Leftist political philosophy?
unanswerable