title: Is there a function to return all single letter colors in Matplotlib?
body: <p>I learnt of <a href="http://matplotlib.org/api/pyplot_api.html#matplotlib.pyplot.colors" rel="noreferrer">matplotlib.pyplot.colors</a> that the basic built-in colors can be represented as a single letter.</p>
  
  <ul>
  <li>b: blue</li>
  <li>g: green</li>
  <li>r: red</li>
  <li>c: cyan</li>
  <li>m: magenta</li>
  <li>y: yellow</li>
  <li>k: black</li>
  <li>w: white</li>
  </ul>
  
  <p>Is there a function in Matplotlib to return those colors?</p>