title: Regex needed for variable expansion in python
body: <p>I am having a variable having a value something like this </p>
  
  <pre><code>var = '${home_${path}}'
  </code></pre>
  
  <p>I want a regex which detects <code>${ any content }</code> recursively.  That is, first I should match <code>${home_${path}}</code> and then <code>${path}</code>. I need this to evaluate the variable content by replacing ${..} with its actual content.</p>