如何在已经存在python2的linux环境上安装python3

[root@localhost install]# pwd
/data/install

[root@localhost install]# cat /etc/redhat-release 
CentOS release 6.3 (Final)

[root@localhost install]# uname -a
Linux localhost 2.6.32-358.6.2.el6.x86_64 #1 SMP Thu May 16 20:59:36 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

[root@localhost install]# wget https://www.python.org/ftp/python/3.4.4/Python-3.4.4.tgz
[root@localhost install]# tar -zxf Python-3.4.4.tgz
[root@localhost install]# cd Python-3.4.4

# 在安装包中有一个README的文件，里面有写如何安装
[root@localhost Python-3.4.4]# ls
aclocal.m4    config.sub  configure.ac  Grammar  install-sh  LICENSE  Makefile.pre.in  Modules  Parser  PCbuild        Python  setup.py
config.guess  configure   Doc           Include  Lib         Mac      Misc             Objects  PC      pyconfig.h.in  README  Tools

[root@localhost Python-3.4.4]# ./configure
[root@localhost Python-3.4.4]# make
[root@localhost Python-3.4.4]# make install

[root@localhost Python-3.4.4]# python3
Python 3.4.4 (default, Jun 27 2016, 07:47:54) 
[GCC 4.4.7 20120313 (Red Hat 4.4.7-16)] on linux
Type "help", "copyright", "credits" or "license" for more information.
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