title: Fill in Area between curves Python
body: <p>How do I fill in the space <strong>beneath</strong> curve &quot;a&quot; (the sloping up line) and <strong>above</strong> &quot;b&quot; (horizontal)? Thank you.</p>
  <pre><code>#Plot data
  sns.set(font_scale = 1.5, style = 'white', rc=None)
  
  fig, ax = plt.subplots(figsize = (15,10))
  
  a = sensitivity.plot(y = 0.2, ax = ax, linestyle = '--', color = 'gray')
  b = sensitivity.plot(y = 0.3, ax = ax, linestyle = '-.', color = 'gray')
  c = sensitivity.plot(y = 0.4, ax = ax, linestyle = ':', color = 'gray')
  d = ax.hlines(y=7.5, xmin=100, xmax=900, colors='black', linestyles='-', lw=2, label='Single Short Line')
  </code></pre>
  <p><strong>Output:</strong></p>
  <p><a href="https://i.stack.imgur.com/Km9hw.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Km9hw.png" alt="enter image description here" /></a></p>