Definition: In this task, you're given a passage, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.
Input: Passage: Born in Constantinople to a civil servant father, Mehmet Cemil Bey, and a mother Ayşe Hamide Hanım, who was a daughter of Sufi shaykh İbrahim Edhem Efendi, he studied law at Darülfünûn-u Şahâne (دار الفنون شهانه), now Istanbul University, and graduated in 1908. He was a legal counsel for the Ottoman Ministry of Foreign Affairs, when he saw the birth of his first son, Nesuhi, on 26 November 1917, in Constantinople (now Istanbul), during the First World War. Taking part in an Ottoman delegation with a mission to search reconciliation with the Nationalists in Ankara, by the end of 1920, changed his destiny. While the two Ottoman Ministers heading the delegation returned to Istanbul after not achieving an understanding with the revolutionaries led by Mustafa Kemal Pasha he chose to join the National Struggle and remained in Ankara, leaving behind his young wife and three-year-old son, Nesuhi. He became an aide to Mustafa Kemal during the Turkish War of Independence and the chief legal counsel of the Turkish delegation to the resulting Treaty of Lausanne in 1923.
 Link Information: The Turkish War of Independence ( "War of Liberation", also known figuratively as İstiklâl Harbi "Independence War" or Millî Mücadele "National Campaign"; 19 May 1919 – 24 July 1923) Question: How many years were there between the beginning of the Turkish War of Independence and the signing of peace treaty that ended the war?
Output:
Answer: 3