title: how to hide axes in matplotlib.pyplot
body: <p>I put the image in a <code>numpy</code> array, and draw it with the following code. How can I tell the program not to draw the axes, like <code>(0, 100, 200...)</code>    </p>
  
  <pre><code>import matplotlib.pyplot as plt
  plt.figure()
  plt.imshow(output_ndarray)
  plt.savefig(output_png)
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/lIzWu.png" rel="noreferrer"><img src="https://i.stack.imgur.com/lIzWu.png" alt="aflw picture"></a></p>