title: Store all characters between parentheses in string
body: <p>I have a string</p>
  
  <pre><code>statement = 'P ∧ (Q ∨ R) ↔ (P ∧ Q) ∨ (P ∧ R)'
  </code></pre>
  
  <p>I want to store each string that is within parentheses, like this:</p>
  
  <pre><code>['Q ∨ R', 'P ∧ Q', 'P ∧ R']
  </code></pre>
  
  <p>How can this be done?</p>