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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 login(self):
 """ Perform IAM cookie based user login. """

        access_token = self._get_access_token()
        try:
            super(IAMSession, self).request(
                'POST',
                self._session_url,
                headers={'Content-Type': 'application/json'},
                data=json.dumps({'access_token': access_token})
            ).raise_for_status()

        except RequestException:
            raise CloudantException(
                'Failed to exchange IAM token with Cloudant')