title: understanding "try" and "except" python
body: <p>For what I have understand till now is, computer will try to run the code in try section and will except stuff mentioned in except part. As soon as computer got something as mentioned in except it will run except code.</p>
  
  <p>So, I tried the following:</p>
  
  <pre><code>try:
      if year // 100:
          print year, "is not a leap year"
  
      else:
          print year, "is not a leap year"
  
  
   except year // 400  and year // 4:
          print "is a leap year"
  </code></pre>
  
  <p>This does not work.</p>
  
  <p>I want to know why it is so?</p>