title: How to get Python3 to find installed module?
body: <p>I'm attempting to install <code>xlsxwriter</code> on CentOS centos-release-7-6.1810.2.el7.centos.x86_64</p>
  
  <p>when I install <code>xlsxwriter</code>:</p>
  
  <pre><code>703404669@bioitutil2:~$ sudo pip3 install xlsxwriter
  Requirement already satisfied: xlsxwriter in /usr/lib64/python3.4/site-packages (1.2.6)
  </code></pre>
  
  <p>and when I attempt to load the module, I get a contradictory message:</p>
  
  <pre><code>703404669@bioitutil2:~$ python3
  Python 3.6.8 (default, Aug  7 2019, 17:28:10) 
  [GCC 4.8.5 20150623 (Red Hat 4.8.5-39)] on linux
  Type "help", "copyright", "credits" or "license" for more information.
  &gt;&gt;&gt; import xlsxwriter
  Traceback (most recent call last):
    File "&lt;stdin&gt;", line 1, in &lt;module&gt;
  ModuleNotFoundError: No module named 'xlsxwriter'
  </code></pre>
  
  <p>I've also tried <code>pip3.6</code>, but get more errors:</p>
  
  <pre><code>703404669@bioitutil2:~$ sudo pip3.6 install xlsxwriter
  Traceback (most recent call last):
    File "/bin/pip3.6", line 16, in &lt;module&gt;
      sys.exit(main())
  TypeError: 'module' object is not callable
  </code></pre>
  
  <p>How can I get python3 to find <code>xlsxwriter</code>?</p>