title: Plot unions of polygons in matplotlib
body: <p>I am trying to plot the union of a couple of polygons in <code>matplotlib</code>, with a certain level of alpha. My current code below has a darker color at the intersections. Would there be anyway to make the intersections the same color with other places?</p>
  
  <pre><code>import matplotlib.pyplot as plt
  
  fig, axs = plt.subplots()
  axs.fill([0, 0, 1, 1], [0, 1, 1, 0], alpha=.25, fc='r', ec='none')
  axs.fill([0.5, 0.5, 1.5, 1.5], [0.5, 1.5, 1.5, 0.5], alpha=.25, fc='r', ec='none')
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/ya64r.png" rel="noreferrer"><img src="https://i.stack.imgur.com/ya64r.png" alt="Generated plot"></a></p>