全新安装 ubuntu gnome 14.04，然后进行 dist-upgrade
我尝试做的第一件事就是为 python 创建虚拟环境
python3 -m venv flask
给我
The virtual environment was not created successfully because ensurepip is not
available. On Debian/Ubuntu systems, you need to install the python3-venv
package using the following command.
apt-get install python3-venv
You may need to use sudo with that command. After installing the python3-venv
package, recreate your virtual environment.
这很奇怪，因为我认为 venv 是默认安装的，但无论如何
sudo apt-get install python3-venv
给我
E: Unable to locate package python3-venv
我错过了什么吗？我的python安装有问题吗？我试图用谷歌搜索是否有回购或我需要的东西，但我找不到。
当我使用
pip install ipython
或者
pip install "ipython[notebook]"
我收到以下错误：
Downloading/unpacking ipython
Downloading ipython-2.3.1-py27-none-any.whl (2.8MB): 2.8MB downloaded
Installing collected packages: ipython
Cleaning up...
Exception:
Traceback (most recent call last):
File "/usr/lib/python2.7/dist-packages/pip/basecommand.py", line 122, in main
status = self.run(options, args)
File "/usr/lib/python2.7/dist-packages/pip/commands/install.py", line 283, in run
requirement_set.install(install_options, global_options, root=options.root_path)
File "/usr/lib/python2.7/dist-packages/pip/req.py", line 1435, in install
requirement.install(install_options, global_options, *args, **kwargs)
File "/usr/lib/python2.7/dist-packages/pip/req.py", line 671, in install
self.move_wheel_files(self.source_dir, root=root)
File "/usr/lib/python2.7/dist-packages/pip/req.py", line 901, in move_wheel_files
pycompile=self.pycompile,
File "/usr/lib/python2.7/dist-packages/pip/wheel.py", line 206, in move_wheel_files
clobber(source, lib_dir, …