Python script to connect to postgresql database

connnect_postgres.py

def connect(self):
    ''' Open a connection to the database '''
    logging.info("Connecting to database '%s'" % config['DB_DBNAME'])
    dirname = os.path.dirname(os.path.realpath(sys.argv[0]))
    DB_PASSWORD_FILE = (dirname + "/.dbpass." + config['DB_HOST'] + "." +
                        config['DB_USER'])
    with open(DB_PASSWORD_FILE) as pwd:
        DB_PASSWORD = pwd.readline().strip()
    self.conn = psycopg2.connect("host='%s' port='%s' dbname='%s' "
                                 "user='%s' password='%s'" % (
                                 config['DB_HOST'], config['DB_PORT'],
                                 config['DB_DBNAME'], config['DB_USER'],
                                 DB_PASSWORD))
    self.cursor = self.conn.cursor()
    self.cursor.execute('set search_path to %s' % config['DB_SCHEMA'])