title: Convering a list into an array of dtype = int64
body: <p>I have a list </p>
  
  <pre><code>y_test  = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
  
  type(y_test)
  Out[597]: list
  </code></pre>
  
  <p>I would like to convert this into an array of dtype <code>int64</code>. </p>
  
  <pre><code>y_test
  Out[598]: array([1, 1, 1, ..., 1, 0, 1], dtype=int64)
  
  type(y_test)
  Out[599]: numpy.ndarray
  
  y_test.shape
  Out[600]: (25000,)
  </code></pre>
  
  <p>Kindly note the shape of the result. 
  Is this something achievable?</p>