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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 group(self, id, expand=None):
 """Get a group Resource from the server. :param id: ID of the group to get :param id: str :param expand: Extra information to fetch inside each resource :type expand: Optional[Any] :rtype: User """

        group = Group(self._options, self._session)
        params = {}
        if expand is not None:
            params['expand'] = expand
        group.find(id, params=params)
        return group