Rename a file in the Mxit user's gallery
        User authentication required with the following scope: 'content/write'

def rename_gallery_file(self, file_id, new_file_name, scope='content/write'):
        """
        Rename a file in the Mxit user's gallery
        User authentication required with the following scope: 'content/write'
        """
        return _put(
            token=self.oauth.get_user_token(scope),
            uri='/user/media/file/' + urllib.quote(file_id),
            data=new_file_name
        )