title: getting a set of numbers with regex in python
body: <p>Suppose that I have the folliwing string</p>
  <pre><code>string = &quot;serial 7's 93-86-79-72-65 very slow, recall 3/3 &quot;
  </code></pre>
  <p>Now, I want to find the set of numbers using regular expressions in Python. Note that the numbers <em>must</em> be preceded by <code>&quot;serial 7's&quot;</code> I have tried the following:</p>
  <pre><code>re.findall('(?&lt;=serial 7\'s )(\d+, )', string)
  re.findall('(?&lt;=serial 7\'s )(\d+, )+', string)
  </code></pre>
  <p>Nothing seems to work. Note that there might be unknown number of integers we are trying to extract. I only want numbers with the specific pattern. Not other numbers that might be scattered within the text.</p>
  <p>Expected output: <code>['93','86','79','72','65']</code></p>