title: unable to create diagonal histogram in seaborn
body: <p>I'm trying to create a diagonal histogram using pairplot() in seaborn, below is my code:</p>
  
  <pre><code>import seaborn as sb
  
  colors = ['#c994c7','#dd1c77','#c51b8a','#fa9fb5','#9ebcda','#feb24c']
  
  ds = sb.load_dataset('titanic')
  sb.pairplot(ds,hue='embark_town',palette=colors,kind='scatter',diag_kind='hist')
  </code></pre>
  
  <p>But I'm getting the following error:</p>
  
  <blockquote>
  <pre><code>TypeError: NumPy boolean subtract, the `-` operator, is deprecated, use the bitwise_xor, the `^` operator, or the logical_xor function instead.
  </code></pre>
  </blockquote>
  
  <p>Although it creates histogram diagonally but it doesn't create any non entity-relationship plots using the kind parameter. the above code works fine when I use 'kde' in diag_kind parameter.</p>