beautifulsoup4-4.6.  Desktop        Documents  hc.war       lxml-3.8.  myblog  Pictures  requests-2.18.  Templates  Videos

code                  Django-1.9.  Downloads  Hellodjango  Music       perl5   Public    software         test.html

[peteryrcc@localhost ~]$ cat test.html

<title>python.............HTML..&lt;h3_....</title>

<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />

<link rel="icon" sizes="any" mask href="//www.baidu.com/img/baidu.svg" />

[peteryrcc@localhost ~]$ a='cat test.html'

[peteryrcc@localhost ~]$ echo $a

cat test.html

[peteryrcc@localhost ~]$ eval a

bash: a: command not found...

[peteryrcc@localhost ~]$ eval $a

<title>python.............HTML..&lt;h3_....</title>

<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />

<link rel="icon" sizes="any" mask href="//www.baidu.com/img/baidu.svg" />

[peteryrcc@localhost ~]$