<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:

def close(self):
        '''Save the cookie jar if needed.'''
        if self._save_filename:
            self._cookie_jar.save(
                self._save_filename,
                ignore_discard=self._keep_session_cookies
            )