question: Who is the maternal grandmother of Bolesław Januszowic?
context: [["Boles\u0142aw Januszowic", ["Boles\u0142aw Januszowic (1385/86 \u2013 ca. 4 May 1424), was a Polish prince member of the House of Piast.", "He was the second son of Duke Janusz I of Warsaw and Danut\u0117 of Lithuania, a daughter of K\u0119stutis."]], ["Hannah Arnold", ["Hannah Arnold, also known as Hannah Waterman King, was the grandmother of Benedict Arnolds children."]], ["G\u00fclbahar Hatun (wife of Mehmed II)", ["G\u00fclbahar Hatun( 1432 \u2013 1492) was the consort of Sultan Mehmed II, and mother of Sultan Bayezid II of the Ottoman Empire and the grandmother of Selim I."]], ["H\u00fcma Hatun", ["H\u00fcma Hatun (1410 \u2012 September 1449) was the fourth wife of Ottoman Sultan Murad II and mother of Mehmed II and the grandmother of Bayezid II."]], ["Hubba bint Hulail", ["Hubba bint Hulail was the grandmother of Hashim ibn' Abd Manaf, thus the great- great- great- grandmother of the Islamic\" Nab\u012b\"( Prophet) Muhammad ibn Abdullah."]], ["Mona Hopton Bell", ["Mona Hopton Bell( 1867- 1940) was a British artist, best known for her portraits of civic figures.", "She was the grandmother of the painter Jean H. Bell."]], ["Kaoru Hatoyama", ["After the elections of 2009, she became more widely known as the grandmother of Prime Minister Yukio Hatoyama and his politician brother Kunio Hatoyama."]], ["Tjuyu", ["Tjuyu( sometimes transliterated as Thuya or Thuyu) was an Egyptian noblewoman and the mother of queen Tiye, and the wife of Yuya.", "She is the grandmother of Akhenaten, and great grandmother of Tutankhamun."]], ["Anne Denman", ["Anne Denman( 1587\u20131661) was born in Olde Hall, Retford, Nottinghamshire.", "Through a fortunate second marriage with Thomas Aylesbury, she became the grandmother of Lady Anne Hyde, Duchess of York and great- grandmother of Queen Mary II and Queen Anne."]], ["Danut\u0117 of Lithuania", ["Danut\u0117 of Lithuania (baptized \"Anna\"; ca.", "1358 \u2013", "26 November 1424), was a Lithuanian princess of the Gediminid dynasty and by marriage Duchess of Warsaw.", "She was a daughter of K\u0119stutis, Grand Duke of Lithuania, and his second wife Birut\u0117."]]]
supporting_facts: [["Boles\u0142aw Januszowic", 1], ["Danut\u0117 of Lithuania", 3]]
evidences: [["Boles\u0142aw Januszowic", "mother", "Danut\u0117 of Lithuania"], ["Danut\u0117 of Lithuania", "mother", "Birut\u0117"]]
answer: Birutė