title: Regex to join numbers when they have spaces between them
body: <p>I'm trying to build a regex that joins numbers in a string when they have spaces between them, ex:</p>
  
  <pre><code>$string = "I want to go home 8890 7463 and then go to 58639 6312 the cinema"
  </code></pre>
  
  <p>The regex should output:</p>
  
  <pre><code>"I want to go home 88907463 and then go to 586396312 the cinema"
  </code></pre>
  
  <p>The regex can be either in python or php language.</p>
  
  <p>Thanks!</p>