title: Regex for password = one number and both lower and uppercase letters and special characters BUT!! no special characters at start or end
body: <p>I'm trying to create a Regex for an html5 pattern in a password input.</p>
  
  <p>The password must contain at least:</p>
  
  <ul>
  <li>1 uppercase letter </li>
  <li>1 lowercase letter </li>
  <li>1 number </li>
  <li>1 special character</li>
  <li>8-20 characters </li>
  <li>Must not start or end with a special character</li>
  </ul>
  
  <p>Any help appreciated</p>