Name the total number of material collected for  justice league of america by george pérez, vol. 2
{'header': ['#', 'Volume line', 'Volume title', 'Creators', 'Material collected', 'Publication date', 'ISBN'], 'page_title': 'DC Comics Classics Library', 'page_id': '', 'types': ['real', 'text', 'text', 'text', 'text', 'text', 'text'], 'id': '1-19534677-1', 'section_title': 'Collections', 'caption': 'Collections', 'rows': [['1', 'Superman', 'Kryptonite Nevermore', "Dennis O'Neil Curt Swan", 'Superman #233-238, #240-242', '2009/01/28', '978-1401220853'], ['2', 'Legion of Super-Heroes', 'The Life and Death of Ferro Lad', 'Jim Shooter Curt Swan, et al.', 'Adventure Comics #346-347, #352-353, #357', '2009/02/18', '978-1401221935'], ['3', 'Batman', 'The Annuals, Vol. 1', 'Bill Finger Edmond Hamilton Dick Sprang , et al.', 'Batman Annual #1-3', '2009/04/22', '978-1401221928'], ['4', 'Swamp Thing', 'Roots of the Swamp Thing', 'Len Wein Berni Wrightson', 'House of Secrets #92 Swamp Thing #1-13', '2009/05/27', '978-1401222369'], ['5', 'The Flash', 'Flash of Two Worlds', 'Gardner Fox Carmine Infantino John Broome', 'The Flash #123, #129, #137, #151, #170, #173', '2009/07/29', '978-1401222987'], ['6', 'Justice League of America', 'Justice League of America by George Pérez, Vol. 1', 'Gerry Conway George Pérez', 'Justice League of America #184-186, #192-194', '2009/08/26', '978-1401223212'], ['7', 'Batman', 'A Death in the Family', 'Jim Starlin Marv Wolfman George Pérez, et al.', 'Batman #426-429, #440-442 The New Titans #60-61', '2009/09/23', '978-1401225162'], ['8', 'Justice League of America', 'Justice League of America by George Pérez, Vol. 2', 'Gerry Conway George Pérez, et al.', 'Justice League of America #193-197, #200', '2010/04/13', '978-1401224509'], ['9', 'Batman', 'The Annuals, Vol. 2', 'Bill Finger', 'Batman Annual #4-7', '2010/08/10', '978-1401227913']], 'name': 'table_19534677_1'}