title: module: duplicate definiton for identifier in: x
body: <p>I typed this code in Dr Racket running on Linux Mint:</p>
  
  <pre><code>lang racket
  
  (define x 2)
  (define x 3)
  </code></pre>
  
  <p>and it shows me this:</p>
  
  <pre><code>module: duplicate definiton for identifier in: x
  </code></pre>
  
  <p>What should I do to be able to redefine a variable?
  (Initially my code was longer but even only this part alone generates error)</p>