我已经尝试了许多可用的解决方案，包括fetch_openml（），但到目前为止没有任何效果，不赞成使用的是什么意思？ 有人可以帮忙解决这个问题吗？
/usr/local/lib/python3.6/dist-packages/sklearn/utils/deprecation.py:77: DeprecationWarning: Function fetch_mldata is deprecated; fetch_mldata was deprecated in version 0.20 and will be removed in version 0.22
warnings.warn(msg, category=DeprecationWarning)
/usr/local/lib/python3.6/dist-packages/sklearn/utils/deprecation.py:77: DeprecationWarning: Function mldata_filename is deprecated; mldata_filename was deprecated in version 0.20 and will be removed in version 0.22
warnings.warn(msg, category=DeprecationWarning)
---------------------------------------------------------------------------
HTTPError Traceback (most recent call last)
<ipython-input-4-24c62b1005d9> in <module>
----> 1 mnist=datasets.fetch_mldata('MNIST original')
/usr/local/lib/python3.6/dist-packages/sklearn/utils/deprecation.py in wrapped(*args, **kwargs)
76 def wrapped(*args, **kwargs):
77 warnings.warn(msg, category=DeprecationWarning)
---> 78 return fun(*args, **kwargs)
79
80 wrapped.__doc__ = self._update_doc(wrapped.__doc__)
/usr/local/lib/python3.6/dist-packages/sklearn/datasets/mldata.py in fetch_mldata(dataname, target_name, data_name, transpose_data, data_home)
131 urlname = MLDATA_BASE_URL % quote(dataname)
132 try:
--> 133 mldata_url = urlopen(urlname)
134 except HTTPError as e:
135 if e.code == 404:
/usr/lib/python3.6/urllib/request.py in urlopen(url, data, timeout, cafile, capath, cadefault, context)
221 else:
222 opener = _opener
--> 223 return opener.open(url, data, timeout)
224
225 def install_opener(opener):
/usr/lib/python3.6/urllib/request.py in open(self, fullurl, data, timeout)
530 for processor in self.process_response.get(protocol, []):
531 meth = getattr(processor, meth_name)
--> 532 response = meth(req, response)
533
534 return response
/usr/lib/python3.6/urllib/request.py in http_response(self, request, response)
640 if not (200 <= code < 300):
641 response = self.parent.error(
--> 642 'http', request, response, code, msg, hdrs)
643
644 return response
/usr/lib/python3.6/urllib/request.py in error(self, proto, *args)
568 if http_err:
569 args = (dict, 'default', 'http_error_default') + orig_args
--> 570 return self._call_chain(*args)
571
572 # XXX probably also want an abstract factory that knows when it makes
/usr/lib/python3.6/urllib/request.py in _call_chain(self, chain, kind, meth_name, *args)
502 for handler in handlers:
503 func = getattr(handler, meth_name)
--> 504 result = func(*args)
505 if result is not None:
506 return result
/usr/lib/python3.6/urllib/request.py in http_error_default(self, req, fp, code, msg, hdrs)
648 class HTTPDefaultErrorHandler(BaseHandler):
649 def http_error_default(self, req, fp, code, msg, hdrs):
--> 650 raise HTTPError(req.full_url, code, msg, hdrs, fp)
651
652 class HTTPRedirectHandler(BaseHandler):
HTTPError: HTTP Error 502: Connection timed out
当我在jupyter笔记本中运行以上代码时，发生此错误。我也在ipython和python3中尝试过，全部在Ubuntu 18.04中进行了