title: Colouring Pie chart Matplotlib.pyplot with hexcode
body: <p>I'm trying to specify the colour of a pie-chart created with matplotlib.pyplot with a hexcode</p>
  
  <p>Example:</p>
  
  <pre><code>import matplotlib.pyplot as plt  
  
  values = [1,2,3]
  
  fig1, ax1 = plt.subplots()
  ax1.pie(values, autopct = '%1.1f%%', colors = '#123456')
  
  plt.savefig('Title.pdf')
  </code></pre>
  
  <p>But everytime this error occurs: </p>
  
  <p>ValueError: to_rgba: Invalid rgba arg "#"<br>
  to_rgb: Invalid rgb arg "#"<br>
  invalid hex color string "#"  </p>
  
  <p>I cant figure out, why this happens. </p>