在cygwin中运行pip install时出错

Question

我试图用以下命令在我的cygwin环境中安装python pymssql模块，但得到以下错误：

Collecting pymssql
  Using cached pymssql-2.1.2.tar.gz
    Complete output from command python setup.py egg_info:
    Download error on https://pypi.python.org/simple/setuptools_git/: unknown error (_ssl.c:2738) -- Some packages may not be found!
    Download error on https://pypi.python.org/simple/setuptools-git/: unknown error (_ssl.c:2738) -- Some packages may not be found!
    Couldn't find index page for 'setuptools_git' (maybe misspelled?)
    Download error on https://pypi.python.org/simple/: unknown error (_ssl.c:2738) -- Some packages may not be found!
    No local packages or download links found for setuptools-git
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-build-epkoy3e7/pymssql/setup.py", line 464, in <module>
        ext_modules = ext_modules(),
      File "/usr/lib/python3.4/distutils/core.py", line 108, in setup
        _setup_distribution = dist = klass(attrs)
      File "/usr/lib/python3.4/site-packages/setuptools/dist.py", line 265, in __init__
        self.fetch_build_eggs(attrs['setup_requires'])
      File "/usr/lib/python3.4/site-packages/setuptools/dist.py", line 310, in fetch_build_eggs
        replace_conflicting=True,
      File "/usr/lib/python3.4/site-packages/pkg_resources/__init__.py", line 830, in resolve
        dist = best[req.key] = env.best_match(req, ws, installer)
      File "/usr/lib/python3.4/site-packages/pkg_resources/__init__.py", line 1075, in best_match
        return self.obtain(req, installer)
      File "/usr/lib/python3.4/site-packages/pkg_resources/__init__.py", line 1087, in obtain
        return installer(requirement)
      File "/usr/lib/python3.4/site-packages/setuptools/dist.py", line 377, in fetch_build_egg
        return cmd.easy_install(req)
      File "/usr/lib/python3.4/site-packages/setuptools/command/easy_install.py", line 623, in easy_install
        raise DistutilsError(msg)
    distutils.errors.DistutilsError: Could not find suitable distribution for Requirement.parse('setuptools-git')
    setup.py: platform.system() => 'CYGWIN_NT-6.1'
    setup.py: platform.architecture() => ('64bit', '')
    setup.py: platform.libc_ver() => ('', '')
    setup.py: Not using bundled FreeTDS
    setup.py: include_dirs = []
    setup.py: library_dirs = ['/usr/local/lib']

我把pip更新到了8.1.1，openssl更新到了1.0.2g。在