title: How to write in Django a custom management command which takes a URL as a parameter?
body: <p>I am learning to write custom management commands in Django. I would like to write a command which would take a given URL as a parameter. Something like:</p>
  
  <pre><code>python manage.py command http://example.com
  </code></pre>
  
  <p>I've read a documentation, but it is not clear to me how to do this.
  But I can write a command saying 'Hello World!';)</p>