title: Creating CKAN extension error: file not found error
body: <p>I'm creating a CKAN extension, following the documentation here:
  <a href="https://docs.ckan.org/en/2.9/extensions/tutorial.html" rel="nofollow noreferrer">https://docs.ckan.org/en/2.9/extensions/tutorial.html</a>. I'm stuck at the step which creates an extension template.</p>
  <p>Running any of the following commands will generate the same error:</p>
  <pre><code># 1. 
  ckan generate extension
  # or 2:
  ckan -c /etc/ckan/default/ckan.ini generate extension
  # or 3:
  ckan -c /etc/ckan/default/ckan.ini generate extension -o /usr/lib/ckan/default/src
  </code></pre>
  <p>...which is an odd error to have, because I know that the directory doesn't exist, I want to create it.</p>
  <pre><code>FileNotFoundError: [Errno 2] No such file or directory: '/usr/lib/ckan/default/src/ckanext-iauthfunctions
  </code></pre>
  <p>Trying with <code>cookiecutter</code> results in:</p>
  <pre><code>cookiecutter: command not found
  </code></pre>
  <p>Related: <a href="https://stackoverflow.com/questions/69732065/creating-a-ckan-extension-error-no-such-command-create">Creating a CKAN Extension Error: No such command &#39;create&#39;</a></p>
  <p>System:</p>
  <ul>
  <li>Ubuntu 20.04</li>
  <li>Python 3.8.10</li>
  </ul>