title: How do I set matplotlib plot to "no fill"?
body: <p>I'd like to superimpose one plot over another (they are polygons, really in some lat/lon space, using geopandas, but the plot is simply derived from matplotlib)</p>
  
  <p>I have:</p>
  
  <pre><code>figZ, axZ = plt.subplots(1, figsize=(11,8.5))
  Sfig = X.plot(ax=axZ, color='white', edgecolor='black', lw=0.7)
  Y.plot(ax=axZ, color='white', edgecolor='black', lw=0.7, alpha=0.3)
  </code></pre>
  
  <p>How do I set <code>Sfig</code>'s <code>color</code> to "no-fill" instead of white? The way it is now it "blurs" my <code>Sfig</code> image (<code>X.plot</code>) by the alpha of the <code>Y.plot</code> one. How do I set "color" to <strong>actually</strong> transparent?</p>