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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 session(self, auth=None):
 """Get a dict of the current authenticated user's session information. :param auth: Tuple of username and password. :type auth: Optional[Tuple[str,str]] :rtype: User """

        url = '{server}{auth_url}'.format(**self._options)

        if isinstance(self._session.auth, tuple) or auth:
            if not auth:
                auth = self._session.auth
            username, password = auth
            authentication_data = {'username': username, 'password': password}
            r = self._session.post(url, data=json.dumps(authentication_data))
        else:
            r = self._session.get(url)

        user = User(self._options, self._session, json_loads(r))
        return user