title: ip address validation in python using regex
body: <p>In the following ip address validation i want to see if it a valid ip address or not how can i do this using the below re</p>
  
  <pre><code>&gt;&gt;&gt; ip="241.1.1.112343434" 
  &gt;&gt;&gt; aa=re.match(r"\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}[^0-9]",ip)
  &gt;&gt;&gt; aa.group()
  Traceback (most recent call last):
  File "&lt;stdin&gt;", line 1, in &lt;module&gt;
  AttributeError: 'NoneType' object has no attribute 'group'
  </code></pre>