title: Docker: Can't locate Tk.pm in @INC (you may need to install the Tk module) on Linux
body: <p>I am trying to run a simple perl gui made using Tk module on a ubuntu:16.04 container using both perl:latest and activestate/circleci-activeperl:latest images.</p>
  <p>I get error <code>Can't locate Tk.pm in @INC (you may need to install the Tk module)</code></p>
  <p>What is the command to install the Tk module on the Linux container environment for perl?</p>
  <p>I have used cpan to install Tk as below</p>
  <pre><code>$ perl -MCPAN -e shell
  cpan&gt; install Tk
  </code></pre>
  <p>I get the below error
  <a href="https://i.stack.imgur.com/QTN9D.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/QTN9D.png" alt="enter image description here" /></a></p>