title: Python: Converting list of tuples(variable size) into array like structure with fixed shape
body: <p>I have a list of tuples like:</p>
  
  <pre><code>a = [(1,2,3), (4,5)]   // np.shape = (2,)
  </code></pre>
  
  <p>And i want to covert it into an array like structure, but of fixed shape, ie</p>
  
  <pre><code>a = [(1,2,3), (4,5,0)] // np.shape = (2,3)
  </code></pre>