title: Sum slices of consecutive values in a NumPy array
body: <p>Let's say I have a numpy array <code>a</code> containing 10 values. Just an example situation here, although I would like to repeat the same for an array with length 100.  </p>
  
  <pre><code>a = np.array([1,2,3,4,5,6,7,8,9,10])
  </code></pre>
  
  <p>I would like to sum the first 5 values followed by the second 5 values and so on and store them in a new empty list say <code>b</code>. </p>
  
  <p>So <code>b</code> would contain <code>b = [15,40]</code>.</p>
  
  <p>How do I go about doing it? </p>