title: Capture a regex in a if condition
body: <p>I would like to capture the match of my regex directly in my if condition. I know it was possible in PHP, but I don't know how to do it in a Pythonic way.
  So I run it twice and it's not sexy at all...</p>
  
  <pre><code>str = 'Test string 178-126-587-0 with a match'
  if re.findall(r'[0-9]{3}-[0-9]{3}-[0-9]{3}-[0-9]', str) != []:
      match = re.findall(r'[0-9]{3}-[0-9]{3}-[0-9]{3}-[0-9]', str)[0]
  </code></pre>