title: simple numpy.sum raises ValueError: 'axis' entry is out of bounds
body: <p>I feel like I'm missing the obvious here, but when I try a really simple numpy.sum usage,</p>
  
  <pre><code>import numpy as np
  np.sum(1,2)
  </code></pre>
  
  <p>I get the following error,</p>
  
  <pre><code>ValueError: 'axis' entry is out of bounds
  </code></pre>
  
  <p>So I tried the following</p>
  
  <pre><code>import numpy as np
  np.sum(1,2, axis = 0)
  </code></pre>
  
  <p>which gives the following error</p>
  
  <pre><code>TypeError: sum() got multiple values for argument 'axis'
  </code></pre>
  
  <p>Anyone have any words of wisdom? I feel like this should be as simple as it gets. Thanks!</p>