title: display err:resource previously defined here
body: <p>When i run my project, display:</p>
  
  <blockquote>
    <p>error: resource previously defined here.
    Message{kind=ERROR, text=error: resource previously defined here.</p>
  </blockquote>
  
  <p><a href="https://i.stack.imgur.com/UEre3.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/UEre3.png" alt="Image of Error"></a></p>