Connect to a sqlite database only if no connection exists. Isolation level
        for the connection is automatically set to autocommit

def connect(self, *args, **kwargs):
        """
        Connect to a sqlite database only if no connection exists. Isolation level
        for the connection is automatically set to autocommit
        """
        self.db = sqlite3.connect(*args, **kwargs)
        self.db.isolation_level = None