От Ръководство за потребителя на MySQLdb :
c.executemany(
"""INSERT INTO breakfast (name, spam, eggs, sausage, price)
VALUES (%s, %s, %s, %s, %s)""",
[
("Spam and Sausage Lover's Plate", 5, 1, 8, 7.95 ),
("Not So Much Spam Plate", 3, 2, 0, 3.95 ),
("Don't Wany ANY SPAM! Plate", 0, 4, 3, 5.95 )
] )
така че във вашия случай:
c.executemany("insert into T (F1,F2) values (%s, %s)",
[('a','b'),('c','d')])