首先我是在python3的环境上面完成的。我保留了python2的版本，然后安装python3的版本。然后在安装scrapy的过程中出现的错误，以及切换python版本后出现的错误。

cd /usr/local/src/wget https://www.python.org/ftp/python/3.4.2/Python-3.4.2.tgztar -xf Python-3.4.2.tgzcd Python-3.4.2./configure --prefix=/usr/local/python3make && make install##将python做一个备份，然后把python3的建立一个软连接mv /usr/bin/python /usr/bin/pythonbakln -fs /usr/local/python3/bin/python3 /usr/bin/python再在终端进入python交互模式，出现的是python3了。[root@lsf ~]# pythonPython 3.4.2 (default, Mar 13 2018, 11:37:48) [GCC 4.8.5 20150623 (Red Hat 4.8.5-16)] on linuxType "help", "copyright", "credits" or "license" for more information.##python升级到3后，yum无法正常使用，此时需要改一个文件[root@lsf ~]# cat /usr/bin/yum#!/usr/bin/python2.7将第一行改为python2.7

二、安装scrapy

##建立pip3的软连接ln -fs /usr/local/python3/bin/pip3 /usr/bin/pip3##yum安装依赖包,可以解决编译过程中出现的许多错误yum install -y gcc openssl-devel libxml2-devel libxslt-devel bzip2-devel bzip2* libffi-devel python-devel openssl-devel pycrypto##用pip3安装pip3 install twisted --upgradepip3 install cryptography pycrypto##安装scrapypip3 install scrapy##建立scrapy软连接ln -fs /usr/local/python3/bin/scrapy /usr/bin/scrapy

三、测试scrapy命令

[root@lsf ~]# scrapyScrapy 1.5.0 - no active projectUsage:  scrapy  [options] [args]Available commands:  bench         Run quick benchmark test  fetch         Fetch a URL using the Scrapy downloader  genspider     Generate new spider using pre-defined templates  runspider     Run a self-contained spider (without creating a project)  settings      Get settings values  shell         Interactive scraping console  startproject  Create new project  version       Print Scrapy version  view          Open URL in browser, as seen by Scrapy  [ more ]      More commands available when run from project directoryUse "scrapy  -h" to see more info about a command##创建一个scrapy项目scrapy startproject myfirstpjt##可能会报错ImportError: cannot import name 'certificate_transparency'pip3 install pip3 --upgrade##再次安装scrapypip3 install scrapy##创建项目成功后，会出现下面的文件[root@lsf test_scrapy]# cd myfirstpjt/[root@lsf myfirstpjt]# lsmyfirstpjt  scrapy.cfg[root@lsf myfirstpjt]# cd myfirstpjt/[root@lsf myfirstpjt]# ls__init__.py  items.py  middlewares.py  pipelines.py  __pycache__  settings.py  spiders

然后就可以直接使用scrapy命令进行项目管理了。