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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def authenticate(self):
 """ Handles authentication, and persists the X-APPLE-WEB-KB cookie so that subsequent logins will not cause additional e-mails from Apple. """


        logger.info("Authenticating as %s", self.user['apple_id'])

        data = dict(self.user)

        # We authenticate every time, so "remember me" is not needed
        data.update({'extended_login': False})

        try:
            req = self.session.post(
                self._base_login_url,
                params=self.params,
                data=json.dumps(data)
            )
        except PyiCloudAPIResponseError as error:
            msg = 'Invalid email/password combination.'
            raise PyiCloudFailedLoginException(msg, error)

        resp = req.json()
        self.params.update({'dsid': resp['dsInfo']['dsid']})

        if not os.path.exists(self._cookie_directory):
            os.mkdir(self._cookie_directory)
        self.session.cookies.save()
        logger.debug("Cookies saved to %s", self._get_cookiejar_path())

        self.data = resp
        self.webservices = self.data['webservices']

        logger.info("Authentication completed successfully")
        logger.debug(self.params)