title: How can I generate a list of node features as Numpy array
body: <p>For a Graph based machine learning task, I need to input a Numpy array in the following format. It's actually an array of array. I tried several options like vstack, concatenate, etc. but nothing works for me. </p>
  
  <p>This is the format I'm having now.</p>
  
  <pre><code>array([[[0., 0., 0., ..., 0., 0., 0.],
          [0., 0., 0., ..., 0., 0., 0.],
          [0., 0., 0., ..., 0., 0., 0.]],
  
         [[0., 0., 0., ..., 0., 0., 0.],
          [0., 0., 0., ..., 0., 0., 0.],
          [0., 0., 0., ..., 0., 0., 0.]]], dtype=float32)
  </code></pre>
  
  <p>The <strong><em>shape</em></strong> of this input is:</p>
  
  <pre><code>(2, 3, 5)
  </code></pre>
  
  <p>But, I need to have a NumPy array with the <strong><em>shape</em></strong> of:</p>
  
  <pre><code>(2,)
  </code></pre>
  
  <p>That means the input should be <strong><em>an array of arrays</em></strong> as below.</p>
  
  <pre><code>array([array([[1., 0., 0., 0., 0.],
         [0., 1., 0., 0., 0.],
         [0., 0., 0., 0., 1.]], dtype=float32),
         array([[1., 0., 0., 0., 0.],
         [1., 0., 0., 0., 0.],
         [0., 0., 0., 0., 1.]], dtype=float32)], dtype=object)
  </code></pre>
  
  <p>Can anyone tell me how to convert the current input (shape:  <code>(2, 3, 5)</code>) into the expected input (shape: <code>(2,)</code>)?</p>
  
  <p>Thanks </p>