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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 delete_folder(self, folder_id, recursive=True):
 """Delete an existing folder Args: folder_id (int):
 ID of the folder to delete. recursive (bool):
 Delete all subfolder if True. Returns: dict. Response from Box. Raises: BoxError: An error response is returned from Box (status_code >= 400). BoxHttpResponseError: Response from Box is malformed. requests.exceptions.*: Any connection related problem. """

        return self.__request("DELETE", "folders/%s" % (folder_id, ),
                        querystring={'recursive': unicode(recursive).lower()})