title: Formatting a mobile number to international format
body: <p>A user can input a phone number in any of the following formats:</p>
  
  <ol>
  <li><p><code>07xxxxxxxxx</code></p></li>
  <li><p><code>00447xxxxxxxxx</code></p></li>
  <li><p><code>447xxxxxxxxx</code></p></li>
  <li><p><code>+447xxxxxxxxx</code></p></li>
  </ol>
  
  <p>I need help in creating a function that will take the number in any of the formats above and return it as international format <code>+447xxxxxxxxx</code>.</p>
  
  <p>This is what I have so far </p>
  
  <pre><code>def _clean_mobile(mobile):
  
    import re
    if re.match('^+44', mobile):
         return mobile
    elif re.match('^44', mobile):
         return "+" + mobile
  </code></pre>