title: How to convert a Python string to a dimensional array or list
body: <p>I have this string:</p>
  
  <pre><code>'(+ (- 5 4) (- 2 1))'
  </code></pre>
  
  <p>and I want it to convert it to an array/list so that the output of the string will be like this:</p>
  
  <pre><code>['+', ['-', 5, 4], ['-', 2, 1]]
  </code></pre>
  
  <p>The parentheses will be a new array inside the array as an element. This is kind of tricky to me since I'm new to this. Thanks in advance!</p>
  
  <p>EDIT: </p>
  
  <p>if i try </p>
  
  <pre><code>'(+ 1 (+ 2 (+ 4 5)))' 
  </code></pre>
  
  <p>the output should be </p>
  
  <pre><code>['+', 1, ['+', 2, ['+', 4, 5]]]
  </code></pre>