title: How to unwrap url.Error returned from http.Client?
body: <p>I'm using <code>net.http.client</code></p>
  
  <p>After sending the request with </p>
  
  <pre class="lang-golang prettyprint-override"><code>resp, err := Client.Do(req)
  </code></pre>
  
  <p>I'm getting the error I want to work with.</p>
  
  <p><code>err.Error()</code> returns an error as string. But I need to work with error as an object. I found the method <code>Unwrap()</code> that seems to be returning an <code>url.Error</code> object, but I'm getting <code>err.Unwrap undefined (type error has no field or method Unwrap)</code></p>
  
  <p>Sorry for dumb question, I'm totally new to golang.</p>