pip在我的ubuntu服务器上停止工作,当我尝试下载任何东西时,会出现以下错误.

$sudo pip install sqlAlchemy
Downloading/unpacking sqlAlchemy
  Cannot fetch index base URL http://pypi.Python.org/simple/
  Could not find any downloads that satisfy the requirement sqlAlchemy
No distributions at all found for sqlAlchemy
Storing complete log in /home/user/.pip/pip.log

以下所有内容都不行

$sudo pip install --upgrade pip 
$sudo apt-get install build-essential

我的/ etc / environment有以下的设置.

http_proxy="http://myproxyhere:portnumberhere/"
HTTP_PROXY="http://myproxyhere:portnumberhere/"

我的/home/user/.pip

------------------------------------------------------------
/usr/bin/pip run on Sat Jun  7 20:08:38 2014
Downloading/unpacking sqlAlchemy

  Getting page http://pypi.python.org/simple/sqlAlchemy
  Could not fetch URL http://pypi.python.org/simple/sqlAlchemy: <urlopen error [Errno 111] Connection refused>
  Will skip URL http://pypi.python.org/simple/sqlAlchemy when looking for download links for sqlAlchemy
  Getting page http://pypi.python.org/simple/
  Could not fetch URL http://pypi.python.org/simple/: <urlopen error [Errno 111] Connection refused>
  Will skip URL http://pypi.python.org/simple/ when looking for download links for sqlAlchemy
  Cannot fetch index base URL http://pypi.python.org/simple/

  URLs to search for versions for sqlAlchemy:
  * http://pypi.python.org/simple/sqlAlchemy/
  Getting page http://pypi.python.org/simple/sqlAlchemy/
  Could not fetch URL http://pypi.python.org/simple/sqlAlchemy/: <urlopen error [Errno 111] Connection refused>
  Will skip URL http://pypi.python.org/simple/sqlAlchemy/ when looking for download links for sqlAlchemy
  Could not find any downloads that satisfy the requirement sqlAlchemy

No distributions at all found for sqlAlchemy

Exception information:
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/pip/basecommand.py",line 126,in main
    self.run(options,args)
  File "/usr/lib/python2.7/dist-packages/pip/commands/install.py",line 223,in run
    requirement_set.prepare_files(finder,force_root_egg_info=self.bundle,bundle=self.bundle)
  File "/usr/lib/python2.7/dist-packages/pip/req.py",line 948,in prepare_files
    url = finder.find_requirement(req_to_install,upgrade=self.upgrade)
  File "/usr/lib/python2.7/dist-packages/pip/index.py",line 152,in find_requirement
    raise DistributionNotFound('No distributions at all found for %s' % req)
DistributionNotFound: No distributions at all found for sqlAlchemy

有人有什么想法可能会出错吗？