title: How to ignore root warnings?
body: <p>I generate monochromatic images and save them using <code>imageio.imwrite</code>. Every time I save a file I get a following warning:</p>
  
  <pre><code>WARNING:root:Lossy conversion from float64 to uint8. Range [-0.24890179009891278, 2.35786261304524]. Convert image to uint8 prior to saving to suppress this warning.
  </code></pre>
  
  <p>I don't care for this "lossy conversion". Everything looks well and works fine. </p>
  
  <p>However, every ~100 generated images I got different warning which I want to catch. Thus I want to ignore the above one.</p>
  
  <p>I tried to ignore it, but even if I call</p>
  
  <pre><code>import warnings
  warnings.simplefilter('ignore')
  </code></pre>
  
  <p>beforehand I still get this warning.</p>