title: How to create two legend objects for a single plot instance?
body: <p>I use the following example code to generate a bar plot.</p>
  
  <pre><code>import numpy as np
  import matplotlib.pyplot as plt
  
  x = np.linspace(0, 5, 5)
  y = np.exp(x)
  w = x[1] - x[0]
  
  colors = ['blue' if idx % 2 == 0 else 'red' for idx in range(len(x))]
  
  fig, ax = plt.subplots()
  ax.bar(x, y, width=w, color=colors, label='sample plot')
  ax.legend()
  plt.show()
  plt.close(fig)
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/3vOuK.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/3vOuK.png" alt="Bar plot"></a></p>
  
  <p>I would like to show both the red and blue colors in the legend object. I can think of 2 visually appealing ideas. The first idea is to create two rectangle objects (one red, the other blue) that are vertically centered about the legend label. The second idea is to overlay half of a rectangle (in red) over the legend object (in blue). But I do not know how to accomplish either of these. I have looked at the matplotlib docs, I'm just confused. How can I go about doing this?</p>