我正在尝试运行在线课程的脚本，并且必须将源代码从python 2更改为python 3语法。在这个脚本中，有一个存档的下载，我已经将其转换为：
url = "https://www.cs.cmu.edu/~./enron/enron_mail_20150507.tgz"
urllib.request.urlretrieve(url, filename="../enron_mail_20150507.tgz")
但是，URL似乎有问题，因为它给了我以下错误：
Traceback (most recent call last):
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/encodings/idna.py", line 165, in encode
raise UnicodeError("label empty or too long")
UnicodeError: label empty or too long
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "ud120_code_py35fork/tools/startup.py", line 37, in <module>
data = urllib.request.urlretrieve("http://...")
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/urllib/request.py", line 187, in urlretrieve
with contextlib.closing(urlopen(url, data)) as fp:
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/urllib/request.py", line 162, in urlopen
return opener.open(url, data, timeout)
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/urllib/request.py", line 465, in open
response = self._open(req, data)
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/urllib/request.py", line 483, in _open
'_open', req)
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/urllib/request.py", line 443, in _call_chain
result = func(*args)
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/urllib/request.py", line 1268, in http_open
return self.do_open(http.client.HTTPConnection, req)
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/urllib/request.py", line 1240, in do_open
h.request(req.get_method(), req.selector, req.data, headers)
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/http/client.py", line 1083, in request
self._send_request(method, url, body, headers)
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/http/client.py", line 1128, in _send_request
self.endheaders(body)
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/http/client.py", line 1079, in endheaders
self._send_output(message_body)
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/http/client.py", line 911, in _send_output
self.send(msg)
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/http/client.py", line 854, in send
self.connect()
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/http/client.py", line 826, in connect
(self.host,self.port), self.timeout, self.source_address)
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/socket.py", line 693, in create_connection
for res in getaddrinfo(host, port, 0, SOCK_STREAM):
File "/home/xiaolong/development/Python/udacity_intro_to_machine_learning/localpython/lib/python3.5/socket.py", line 732, in getaddrinfo
for res in _socket.getaddrinfo(host, port, family, type, proto, flags):
UnicodeError: encoding with 'idna' codec failed (UnicodeError: label empty or too long)
我已尝试使用~和.替换网址中的%7E和%2E，但这根本没有帮助。
网址有什么问题，我该如何解决？