title: Prepend element to numpy array
body: <p>I have the following numpy array</p>
  
  <pre><code>import numpy as np
  
  X = np.array([[5.], [4.], [3.], [2.], [1.]])
  </code></pre>
  
  <p>I want to insert <code>[6.]</code> at the beginning.
  I've tried:</p>
  
  <pre><code>X = X.insert(X, 0)
  </code></pre>
  
  <p>how do I insert into X?</p>