1 import sqlite3

     2 

     3 con = sqlite3.connect(":memory:")

     4 con.execute("create table person (id integer primary key, firstname varchar unique)")

     5 

     6 # Successful, con.commit() is called automatically afterwards

     7 with con:

     8     con.execute("insert into person(firstname) values (?)", ("Joe",))

     9 

    10 # con.rollback() is called after the with block finishes with an exception, the

    11 # exception is still raised and must be catched

    12 try:

    13     with con:

    14         con.execute("insert into person(firstname) values (?)", ("Joe",))

    15 except sqlite3.IntegrityError:

    16     print "couldn't add Joe twice"