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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 get_folder(self, folder):
 """ Return the details for a folder :calls: `GET /api/v1/folders/:id \ <https://canvas.instructure.com/doc/api/files.html#method.folders.show>`_ :param folder: The object or ID of the folder to retrieve. :type folder: :class:`canvasapi.folder.Folder` or int :rtype: :class:`canvasapi.folder.Folder` """

        folder_id = obj_or_id(folder, "folder", (Folder,))

        response = self.__requester.request(
            'GET',
            'folders/{}'.format(folder_id)
        )
        return Folder(self.__requester, response.json())