title: How to start a timer once a key is pressed
body: <p>Right now, I have this:</p>
  
  <pre><code>score = time.time() - start_time
  score = round(score,2)
  </code></pre>
  
  <p>What this does is start the timer once the program is run but I'd like to know how to start the timer once the user presses the enter key. And if it isn't too much trouble, I'd like it to tie in with this:</p>
  
  <pre><code>root.bind("&lt;Return&gt;", startGame)
  </code></pre>
  
  <p>That line of code starts the game(not program) when enter is pressed and I'd like to know how to start the timer at the same time as this.</p>