title: Concatenate the nested arrays within a single 2d array, element-wise
body: <p>I have a numpy array like this:</p>
  <pre><code>array = [[1, 3, 5, 7], [2, 4, 6, 8]]
  </code></pre>
  <p>I would like to concatenate them element-wise. Most of the solutions I have found are able to do this with two separate 2d arrays, but I would like to do this within a single 2d array.</p>
  <p>Desired output:</p>
  <pre><code>array = [[1, 2], [3, 4], [5, 6], [7, 8]]
  </code></pre>