title: use matplotlib color map for color cycle
body: <p>If I create colors by e.g:</p>
  <pre><code>import numpy as np
  from matplotlib import pyplot as plt
  
  n = 6
  color = plt.cm.coolwarm(np.linspace(0.1,0.9,n))
  color
  </code></pre>
  <p>color is a numpy array:</p>
  <pre><code>array([[ 0.34832334,  0.46571115,  0.88834616,  1.        ],
         [ 0.56518158,  0.69943844,  0.99663507,  1.        ],
         [ 0.77737753,  0.84092121,  0.9461493 ,  1.        ],
         [ 0.93577377,  0.8122367 ,  0.74715647,  1.        ],
         [ 0.96049006,  0.61627642,  0.4954666 ,  1.        ],
         [ 0.83936494,  0.32185622,  0.26492398,  1.        ]])
  </code></pre>
  <p>However, If I plug in the RGB values (without the alpha value 1) as tuples in my <code>.mplstyle</code> file (<code>map(tuple,color[:,0:-1])</code>), I get an error similar to this one:</p>
  <pre><code>in file &quot;/home/moritz/.config/matplotlib/stylelib/ggplot.mplstyle&quot;
      Key axes.color_cycle: [(0.34832334141176474 does not look like a color arg
    (val, error_details, msg))
  </code></pre>
  <p>Any ideas why?</p>