title: Regular expression can't match multiple groups of the same type
body: <p>I'm playing with Regex's in python. I know there is a ton of documentation on this. But I just can't understand this apparently simple example:</p>
  
  <p>On this code:</p>
  
  <pre><code>import re
  phoneNumRegex = re.compile(r'(\d\d\d)*')
  mo = phoneNumRegex.search('My number is 415-555-4242. 423-531-5412')
  print(mo.group())
  </code></pre>
  
  <p>I'm expecting to get the output:</p>
  
  <pre><code>415, 555, 423, 531
  </code></pre>
  
  <p>However the program only returns an empty string(nothing). My logic was to specify that I want a group of 3 digits and then the <code>*</code> specifies to match this kind of group <strong>0</strong> or <strong>'n'</strong> times. Since I have multiple 3 digit groups in my string I was expecting to get all of them printed. What am I doing wrong?I tried with the <code>+</code> as well instead of <code>*</code> which by my understanding is supposed to find the group at least once. If I do that it only prints the first group and not all as I would expect. How should I write this to get all 3 digit groups printed?</p>