title: How to get the sub string from the start until the second last comma?
body: <p>From a string like this:</p>
  
  <pre><code>$a = "Viale Giulio Cesare, 137, Roma, RM, Italia";
  </code></pre>
  
  <p>I need to get the string until tne penultimate comma:</p>
  
  <pre><code>$b = "Viale Giulio Cesare, 137, Roma";
  </code></pre>
  
  <p>How can I remove everything finding the penultimate comma?</p>