Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-vqeCP7/Django/

这个是使用pip安装django的报错

root@ubuntu:/# pip install Django
Collecting Django
Using cached Django-2.0.tar.gz
Complete output from command python setup.py egg_info:
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/tmp/pip-build-vqeCP7/Django/setup.py", line 32, in <module>
version = __import__('django').get_version()
File "django/__init__.py", line 1, in <module>
from django.utils.version import get_version
File "django/utils/version.py", line 61, in <module>
@functools.lru_cache()
AttributeError: 'module' object has no attribute 'lru_cache'

----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-vqeCP7/Django/

错误的原因：pip版本是py2.7的管理器，而pip install django 默认是安装django的最新版本

root@ubuntu:/# pip --version
pip 9.0.1 from /usr/local/lib/python2.7/dist-packages (python 2.7)

django的最新版本要支持py3，所以要用pip3（py3的包管理器）安装

root@ubuntu:/# pip3 --version
pip 8.1.1 from /usr/lib/python3/dist-packages (python 3.5)
root@ubuntu:/# pip3 install django
Collecting django
Downloading Django-2.0-py3-none-any.whl (7.1MB)
100% |████████████████████████████████| 7.1MB 190kB/s
Collecting pytz (from django)
Downloading pytz-2017.3-py2.py3-none-any.whl (511kB)
100% |████████████████████████████████| 512kB 2.6MB/s
Installing collected packages: pytz, django
Successfully installed django-2.0 pytz-2017.3          #2.0版本需要py3支持

而py2想安装之前版本的django则需要指定版本

root@ubuntu:/# pip install django==1.10.6
Collecting django==1.10.6
Downloading Django-1.10.6-py2.py3-none-any.whl (6.8MB)
100% |████████████████████████████████| 6.8MB 135kB/s
Installing collected packages: django
Successfully installed django-1.10.6
root@ubuntu:/# pip --version
pip 9.0.1 from /usr/local/lib/python2.7/dist-packages (python 2.7)