title: How to sort a python list?
body: <p>I have a python nested list of following format. I need to sort the list based on the third entry.</p>
  
  <pre><code> interactions = [[0 for x in xrange(3)] for x in xrange(3) ]
   interactions[0] = 'TP53', 'BRCA2', 0.5
   interactions[1] = 'AGT' , 'PCALM', 0.8
   interactions[2] = 'BRCA1', 'BRCA2',0.2
  </code></pre>
  
  <p>I want to sort the list based on the third entry, means the floating point value. Please suggest one efficient method.</p>