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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 _fetch_credentials(self, session):
 """Fetch the endpoint URI and authorization token for this session. Those two information are the basis for all future calls to the Swift (OpenStack) API for the storage container. :param keystoneclient.Session session: The session object to use for queries. :raises keystoneclient.exceptions.AuthorizationFailure: if something goes wrong. """


        headers = {
            'Authorization': 'Bearer {0}'.format(self.access_token),
        }

        r = session.get("https://api.hubic.com/1.0/account/credentials",
                        headers=headers,
                        authenticated=False)
        response = r.json()

        # if we get an error here, the OpenStack SDK will take care to try
        # again for us.
        if 'error' in response:
            raise AuthorizationFailure()

        self.endpoint   = response['endpoint']
        self.auth_token = response['token']