What's the season number of the episode viewed by 3.19 million people in the US?
{'header': ['No. in series', 'No. in season', 'Title', 'Directed by', 'Written by', 'Original air date', 'Production code', 'U.S. viewers (million)'], 'page_title': '', 'page_id': '', 'types': ['real', 'real', 'text', 'text', 'text', 'text', 'text', 'text'], 'id': '1-18268826-1', 'section_title': '', 'caption': '', 'rows': [['23', '1', '"In My Time of Dying"', 'Kim Manners', 'Eric Kripke', 'September28,2006', '3T5501', '3.93'], ['24', '2', '"Everybody Loves a Clown"', 'Phil Sgriccia', 'John Shiban', 'October5,2006', '3T5502', '3.34'], ['25', '3', '"Bloodlust"', 'Robert Singer', 'Sera Gamble', 'October12,2006', '3T5503', '3.78'], ['26', '4', '"Children Shouldn\'t Play with Dead Things"', 'Kim Manners', 'Raelle Tucker', 'October19,2006', '3T5504', '3.29'], ['27', '5', '"Simon Said"', 'Tim Lacofano', 'Ben Edlund', 'October26,2006', '3T5505', '3.65'], ['28', '6', '"No Exit"', 'Kim Manners', 'Matt Witten', 'November2,2006', '3T5506', '3.38'], ['29', '7', '"The Usual Suspects"', 'Mike Rohl', 'Cathryn Humphris', 'November9,2006', '3T5507', '3.19'], ['30', '8', '"Crossroad Blues"', 'Steve Boyum', 'Sera Gamble', 'November16,2006', '3T5508', '3.16'], ['31', '9', '"Croatoan"', 'Robert Singer', 'John Shiban', 'December7,2006', '3T5509', '3.12'], ['32', '10', '"Hunted"', 'Rachel Talalay', 'Raelle Tucker', 'January11,2007', '3T5510', '3.24'], ['33', '11', '"Playthings"', 'Charles Beeson', 'Matt Witten', 'January18,2007', '3T5511', '3.44'], ['34', '12', '"Nightshifter"', 'Phil Sgriccia', 'Ben Edlund', 'January25,2007', '3T5512', '3.42'], ['35', '13', '"Houses of the Holy"', 'Kim Manners', 'Sera Gamble', 'February1,2007', '3T5513', '3.37'], ['36', '14', '"Born Under a Bad Sign"', 'J. Miller Tobin', 'Cathryn Humphris', 'February8,2007', '3T5514', '2.84'], ['37', '15', '"Tall Tales"', 'Bradford May', 'John Shiban', 'February15,2007', '3T5515', '3.03'], ['38', '16', '"Roadkill"', 'Charles Beeson', 'Raelle Tucker', 'March15,2007', '3T5516', '3.52'], ['39', '17', '"Heart"', 'Kim Manners', 'Sera Gamble', 'March22,2007', '3T5517', '3.38'], ['40', '18', '"Hollywood Babylon"', 'Phil Sgriccia', 'Ben Edlund', 'April19,2007', '3T5518', '3.25'], ['41', '19', '"Folsom Prison Blues"', 'Mike Rohl', 'John Shiban', 'April26,2007', '3T5519', '3.33'], ['42', '20', '" What Is and What Should Never Be "', 'Eric Kripke', 'Raelle Tucker', 'May3,2007', '3T5520', '3.11']], 'name': 'table_18268826_1'}