from pysqlite2 import dbapi2 as sqlite3 import apsw apsw_con = apsw.Connection(":memory:") apsw_con.createscalarfunction("times_two", lambda x: 2*x, 1) # Create pysqlite connection from APSW connection con = sqlite3.connect(apsw_con) result = con.execute("select times_two(15)").fetchone()[0] assert result == 30 con.close()