Who is a Polish politician that was also famous for performing Piano Concerto No. 4 by Anton Rubinstein?
Ignacy Jan Paderewski Ignacy Jan Paderewski, GBE (] ; 18 November [O.S. 6 November] 1860  – 29 June 1941) was a Polish pianist and composer, politician and spokesman for Polish independence. He was a favorite of concert audiences around the world. His musical fame opened access to diplomacy and the media.
Janusz Lewandowski Janusz Antoni Lewandowski (; born 13 June 1951) is a Polish politician and economist belonging to the Gdańsk liberals group, and a former member of the European Parliament (elected on 13 June 2004), Chairman of the Committee on Budgets. On 27 November 2009 he obtained the post of Budget and Financial Programming Commissioner of the European Commission and is affiliated to the European People's Party (EPP).