pip install package 時若遇到 AttributeError: _DistInfoDistribution__dep_map

pip install package 時若遇到 AttributeError: _DistInfoDistribution__dep_map 時，那表示你的 pip 跟 setuptools 可能版本不合

Exception:

Traceback (most recent call last):

  File "/usr/local/opt/pyenv/versions/3.4.2/lib/python3.4/site-packages/pip/_vendor/pkg_resources.py", line 2482, in _dep_map

    return self.__dep_map

  File "/usr/local/opt/pyenv/versions/3.4.2/lib/python3.4/site-packages/pip/_vendor/pkg_resources.py", line 2344, in __getattr__

    raise AttributeError(attr)

AttributeError: _DistInfoDistribution__dep_map

During handling of the above exception, another exception occurred:

Traceback (most recent call last):

  File "/usr/local/opt/pyenv/versions/3.4.2/lib/python3.4/site-packages/pip/_vendor/pkg_resources.py", line 2473, in _parsed_pkg_info

    return self._pkg_info

  File "/usr/local/opt/pyenv/versions/3.4.2/lib/python3.4/site-packages/pip/_vendor/pkg_resources.py", line 2344, in __getattr__

    raise AttributeError(attr)

AttributeError: _pkg_info

During handling of the above exception, another exception occurred:

Traceback (most recent call last):

  File "/usr/local/opt/pyenv/versions/3.4.2/lib/python3.4/site-packages/pip/basecommand.py", line 122, in main

    status = self.run(options, args)

  File "/usr/local/opt/pyenv/versions/3.4.2/lib/python3.4/site-packages/pip/commands/install.py", line 278, in run

    requirement_set.prepare_files(finder, force_root_egg_info=self.bundle, bundle=self.bundle)

  File "/usr/local/opt/pyenv/versions/3.4.2/lib/python3.4/site-packages/pip/req.py", line 1265, in prepare_files

    req_to_install.extras):

  File "/usr/local/opt/pyenv/versions/3.4.2/lib/python3.4/site-packages/pip/_vendor/pkg_resources.py", line 2291, in requires

    dm = self._dep_map

  File "/usr/local/opt/pyenv/versions/3.4.2/lib/python3.4/site-packages/pip/_vendor/pkg_resources.py", line 2484, in _dep_map

    self.__dep_map = self._compute_dependencies()

  File "/usr/local/opt/pyenv/versions/3.4.2/lib/python3.4/site-packages/pip/_vendor/pkg_resources.py", line 2506, in _compute_dependencies

    for req in self._parsed_pkg_info.get_all('Requires-Dist') or []:

  File "/usr/local/opt/pyenv/versions/3.4.2/lib/python3.4/site-packages/pip/_vendor/pkg_resources.py", line 2476, in _parsed_pkg_info

    self._pkg_info = Parser().parsestr(self.get_metadata(self.PKG_INFO))

  File "/usr/local/opt/pyenv/versions/3.4.2/lib/python3.4/site-packages/pip/_vendor/pkg_resources.py", line 1366, in get_metadata

    return self._get(self._fn(self.egg_info,name)).decode("utf-8")

  File "/usr/local/opt/pyenv/versions/3.4.2/lib/python3.4/site-packages/pip/_vendor/pkg_resources.py", line 1470, in _get

    stream = open(path, 'rb')

請試著更新 setuptools

pip install --upgrade setuptools
pip install --upgrade distribute

然後再安裝一次試試，問題應該可以解決，詳細問題原因可能出在 pip （未研究，不太確定）