pip3安装无法正常工作-没有名为"pip._vendor.pkg_resources"的模块

当尝试使用pip3 install packageName(或sudo pip3 install packageName)为Python 3(在Ubuntu中)安装软件包时，出现以下错误消息:

When trying to install a package for Python 3 (in Ubuntu), using pip3 install packageName (or sudo pip3 install packageName), I get the following error message:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/pip/_vendor/__init__.py", line 33, in vendored
    __import__(vendored_name, globals(), locals(), level=0)
ImportError: No module named 'pip._vendor.pkg_resources'

我已经阅读了几天，并尝试了以下方法，但没有成功:

I have been reading for days and have tried the following WITHOUT any success:

1. 使用以下代码卸载并重新安装pip3:sudo apt-get remove python3-pip，然后是sudo apt-get install python3-pip.几篇文章中建议这样做，有时pip3不能为Ubuntu正确安装.但是，它没有用.
2. 其他帖子建议这是一个ssl软件包问题，如果ssl软件包未在Python3上加载，那就是问题.但是，以下命令不会引发任何错误:python3 -c "import ssl".
3. 其他一些帖子表明问题出在requests软件包.然后，我尝试了sudo apt-get remove python3-requests，然后又尝试了sudo apt-get install python3-requests，但都没有结果.

1. Un-installing and re-installing pip3 using the following code: sudo apt-get remove python3-pip followed by sudo apt-get install python3-pip. This was suggested in several posts that say that sometimes pip3 doesn't install properly for Ubuntu. However, it didn't work.
2. Other post suggested it was an ssl package problem and that if the ssl package doesn't load on Python3, that's the issue. However the following command does not raise any error: python3 -c "import ssl".
3. Some other post suggested the problem was with the requests package. I then tried sudo apt-get remove python3-requests followed by sudo apt-get install python3-requests also to no avail.

您可能需要的其他信息:

Other information you may need:

• pip3 --version给了我上面报告的相同错误.

• dpkg -L python3-pip给了我以下信息:

• pip3 --version gives me the same error reported above.

• dpkg -L python3-pip gives me the following information:

/.
/usr
/usr/lib
/usr/lib/python3
/usr/lib/python3/dist-packages
/usr/lib/python3/dist-packages/pip-8.1.1.egg-info
/usr/lib/python3/dist-packages/pip-8.1.1.egg-info/PKG-INFO
/usr/lib/python3/dist-packages/pip-8.1.1.egg-info/dependency_links.txt
/usr/lib/python3/dist-packages/pip-8.1.1.egg-info/not-zip-safe
/usr/lib/python3/dist-packages/pip-8.1.1.egg-info/requires.txt
/usr/lib/python3/dist-packages/pip-8.1.1.egg-info/entry_points.txt
/usr/lib/python3/dist-packages/pip-8.1.1.egg-info/top_level.txt
/usr/lib/python3/dist-packages/pip
/usr/lib/python3/dist-packages/pip/baseparser.py
/usr/lib/python3/dist-packages/pip/__main__.py
/usr/lib/python3/dist-packages/pip/req
/usr/lib/python3/dist-packages/pip/req/req_set.py
/usr/lib/python3/dist-packages/pip/req/req_install.py
/usr/lib/python3/dist-packages/pip/req/__init__.py
/usr/lib/python3/dist-packages/pip/req/req_file.py
/usr/lib/python3/dist-packages/pip/req/req_uninstall.py
/usr/lib/python3/dist-packages/pip/index.py
/usr/lib/python3/dist-packages/pip/status_codes.py
/usr/lib/python3/dist-packages/pip/utils
/usr/lib/python3/dist-packages/pip/utils/setuptools_build.py
/usr/lib/python3/dist-packages/pip/utils/appdirs.py
/usr/lib/python3/dist-packages/pip/utils/outdated.py
/usr/lib/python3/dist-packages/pip/utils/ui.py
/usr/lib/python3/dist-packages/pip/utils/logging.py
/usr/lib/python3/dist-packages/pip/utils/encoding.py
/usr/lib/python3/dist-packages/pip/utils/deprecation.py
/usr/lib/python3/dist-packages/pip/utils/__init__.py
/usr/lib/python3/dist-packages/pip/utils/filesystem.py
/usr/lib/python3/dist-packages/pip/utils/hashes.py
/usr/lib/python3/dist-packages/pip/utils/build.py
/usr/lib/python3/dist-packages/pip/compat
/usr/lib/python3/dist-packages/pip/compat/dictconfig.py
/usr/lib/python3/dist-packages/pip/compat/__init__.py
/usr/lib/python3/dist-packages/pip/compat/ordereddict.py
/usr/lib/python3/dist-packages/pip/models
/usr/lib/python3/dist-packages/pip/models/index.py
/usr/lib/python3/dist-packages/pip/models/__init__.py
/usr/lib/python3/dist-packages/pip/vcs
/usr/lib/python3/dist-packages/pip/vcs/bazaar.py
/usr/lib/python3/dist-packages/pip/vcs/subversion.py
/usr/lib/python3/dist-packages/pip/vcs/mercurial.py
/usr/lib/python3/dist-packages/pip/vcs/__init__.py
/usr/lib/python3/dist-packages/pip/vcs/git.py
/usr/lib/python3/dist-packages/pip/cmdoptions.py
/usr/lib/python3/dist-packages/pip/basecommand.py
/usr/lib/python3/dist-packages/pip/commands
/usr/lib/python3/dist-packages/pip/commands/completion.py
/usr/lib/python3/dist-packages/pip/commands/install.py
/usr/lib/python3/dist-packages/pip/commands/hash.py
/usr/lib/python3/dist-packages/pip/commands/uninstall.py
/usr/lib/python3/dist-packages/pip/commands/__init__.py
/usr/lib/python3/dist-packages/pip/commands/list.py
/usr/lib/python3/dist-packages/pip/commands/search.py
/usr/lib/python3/dist-packages/pip/commands/show.py
/usr/lib/python3/dist-packages/pip/commands/download.py
/usr/lib/python3/dist-packages/pip/commands/wheel.py
/usr/lib/python3/dist-packages/pip/commands/freeze.py
/usr/lib/python3/dist-packages/pip/commands/help.py
/usr/lib/python3/dist-packages/pip/_vendor
/usr/lib/python3/dist-packages/pip/_vendor/__init__.py
/usr/lib/python3/dist-packages/pip/operations
/usr/lib/python3/dist-packages/pip/operations/__init__.py
/usr/lib/python3/dist-packages/pip/operations/freeze.py
/usr/lib/python3/dist-packages/pip/__init__.py
/usr/lib/python3/dist-packages/pip/locations.py
/usr/lib/python3/dist-packages/pip/pep425tags.py
/usr/lib/python3/dist-packages/pip/exceptions.py
/usr/lib/python3/dist-packages/pip/download.py
/usr/lib/python3/dist-packages/pip/wheel.py
/usr/share
/usr/share/man
/usr/share/man/man1
/usr/share/man/man1/pip3.1.gz
/usr/share/doc
/usr/share/doc/python3-pip
/usr/share/doc/python3-pip/copyright
/usr/bin
/usr/bin/pip3
/usr/share/doc/python3-pip/changelog.Debian.gz

如何使pip3工作?

注意:Python2的pip正常工作.

NOTE: pip for Python2 works just fine.

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1. 在Python3中尝试import setuptools时，出现以下错误:

1. When trying to import setuptools in Python3 I get the following error:

    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
      File "/usr/lib/python3/dist-packages/setuptools/__init__.py", line 11, in <module>
        from setuptools.extern.six.moves import filterfalse, map
      File "/usr/lib/python3/dist-packages/setuptools/extern/__init__.py", line 1, in <module>
        from pkg_resources.extern import VendorImporter
      File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2927, in <module>
        @_call_aside
      File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2913, in _call_aside
        f(*args, **kwargs)
      File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2952, in _initialize_master_working_set
        add_activation_listener(lambda dist: dist.activate())
      File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 956, in subscribe
        callback(dist)
      File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2952, in <lambda>
        add_activation_listener(lambda dist: dist.activate())
      File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2515, in activate
        declare_namespace(pkg)
      File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2097, in declare_namespace
        _handle_ns(packageName, path_item)
      File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2047, in _handle_ns
        _rebuild_mod_path(path, packageName, module)
      File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2066, in _rebuild_mod_path
        orig_path.sort(key=position_in_sys_path)
    AttributeError: '_NamespacePath' object has no attribute 'sort'

1. 在终端中运行以下命令sed -n '31,37p' < /usr/lib/python3/dist-packages/pip/_vendor/__init__.py时，得到以下信息:

try:
    __import__(vendored_name, globals(), locals(), level=0)
except ImportError:
    try:
        __import__(modulename, globals(), locals(), level=0)
    except ImportError:

=========================================

===========================================

我的python3 --version是Python 3.5.2.

使用代码ls /usr/lib/python3/dist-packages获得的已安装软件包的列表.

List of installed packages obtained running the code ls /usr/lib/python3/dist-packages.

apport
apport_python_hook.py
apt
aptdaemon
apt_inst.cpython-35m-x86_64-linux-gnu.so
apt_pkg.cpython-35m-x86_64-linux-gnu.so
aptsources
AptUrl
apturl-0.5.2.egg-info
beautifulsoup4-4.4.1.egg-info
blinker
blinker-1.3.egg-info
Brlapi-0.6.4.egg-info
brlapi.cpython-35m-x86_64-linux-gnu.so
bs4
cairo
_cffi_backend.cpython-35m-x86_64-linux-gnu.so
chardet
chardet-2.3.0.egg-info
checkbox_support
checkbox_support-0.22.egg-info
CommandNotFound
command_not_found-0.3.egg-info
cryptography
cryptography-1.2.3.egg-info
cups.cpython-35m-x86_64-linux-gnu.so
cupsext.cpython-35m-x86_64-linux-gnu.so
curl
cycler-0.9.0.egg-info
cycler.py
dateutil
dbus
_dbus_bindings.cpython-35m-x86_64-linux-gnu.so
_dbus_glib_bindings.cpython-35m-x86_64-linux-gnu.so
deb822.py
debconf.py
debian
debian_bundle
decorator-4.0.6.egg-info
decorator.py
defer
defer-1.0.6.egg-info
DistUpgrade
easy_install.py
feedparser-5.1.3.egg-info
feedparser.py
feedparser_sgmllib3.py
gi
guacamole
guacamole-0.9.2.egg-info
hpmudext.cpython-35m-x86_64-linux-gnu.so
html5lib
html5lib-0.999.egg-info
httplib2
httplib2-0.9.1.egg-info
idna
idna-2.0.egg-info
janitor
jinja2
Jinja2-2.8.egg-info
jwt
LanguageSelector
language_selector-0.1.egg-info
language_support_pkgs.py
louis
louis-2.6.4.egg-info
lsb_release.py
lxml
lxml-3.5.0.egg-info
mako
Mako-1.0.3.egg-info
markupsafe
MarkupSafe-0.23.egg-info
matplotlib
matplotlib-1.5.1.egg-info
matplotlib-1.5.1-nspkg.pth
mpl_toolkits
networkx
networkx-1.11.egg-info
numexpr
numexpr-2.4.3.egg-info
numpy
numpy-1.11.0.egg-info
NvidiaDetector
oauthlib
oauthlib-1.0.3.egg-info
Onboard
onboard-1.2.0.egg-info
orca
padme
padme-1.1.1.egg-info
pandas
pandas-0.17.1.egg-info
pcardext.cpython-35m-x86_64-linux-gnu.so
pexpect
pexpect-4.0.1.egg-info
PIL
Pillow-3.1.2.egg-info
pip
pip-8.1.1.egg-info
pkg_resources
plotly
plotly-1.9.5.egg-info
problem_report.py
ptyprocess
ptyprocess-0.5.egg-info
pyasn1
pyasn1-0.1.9.egg-info
pyatspi
__pycache__
pycups-1.9.73.egg-info
pycurl-7.43.0.egg-info
pycurl.cpython-35m-x86_64-linux-gnu.so
pygobject-3.20.0.egg-info
pygtkcompat
PyJWT-1.3.0.egg-info
pylab.py
pyparsing-2.0.3.egg-info
pyparsing.py
python_apt-1.1.0.b1_ubuntu0.16.04.1.egg-info
python_dateutil-2.4.2.egg-info
python_debian-0.1.27.egg-info
python_systemd-231.egg-info
pytz
pytz-2014.10.egg-info
pyxdg-0.25.egg-info
PyYAML-3.11.egg-info
Quirks
reportlab
reportlab-3.3.0.egg-info
requests
requests-2.9.1.egg-info
scanext.cpython-35m-x86_64-linux-gnu.so
scipy
scipy-0.17.0.egg-info
sessioninstaller
sessioninstaller-0.0.0.egg-info
setuptools
setuptools-20.7.0.egg-info
six-1.10.0.egg-info
six.py
softwareproperties
speechd
speechd_config
systemd
system_service-0.3.egg-info
tables
tables-3.2.2.egg-info
UbuntuDrivers
ubuntu_drivers_common-0.0.0.egg-info
UbuntuSystemService
ufw
ufw-0.35.egg-info
unattended_upgrades-0.1.egg-info
unity_scope_calculator-0.1.egg-info
unity_scope_chromiumbookmarks-0.1.egg-info
unity_scope_colourlovers-0.1.egg-info
unity_scope_devhelp-0.1.egg-info
unity_scope_firefoxbookmarks-0.1.egg-info
unity_scope_gdrive-0.7.egg-info
unity_scope_manpages-0.1.egg-info
unity_scope_openclipart-0.1.egg-info
unity_scope_texdoc-0.1.egg-info
unity_scope_tomboy-0.1.egg-info
unity_scope_virtualbox-0.1.egg-info
unity_scope_yelp-0.1.egg-info
unity_scope_zotero-0.1.egg-info
unohelper.py
uno.py
UpdateManager
urllib3
urllib3-1.13.1.egg-info
usbcreator
usb_creator-0.3.0.egg-info
wheel
wheel-0.29.0.egg-info
xdg
xdiagnose
xdiagnose-3.8.4.1.egg-info
xkit
xkit-0.0.0.egg-info
xlsxwriter
XlsxWriter-0.7.3.egg-info
yaml
_yaml.cpython-35m-x86_64-linux-gnu.so