code: def register_custom_colormaps():
      
      if not HAS_MPL:
          return ()
      makemap = LinearSegmentedColormap.from_list
      for name, val in custom_colormap_data.items():
          cm1 = np.array(val).transpose().astype('f8')/256.0
          cm2 = cm1[::-1]
          nam1 = name
          nam2 = '%s_r' % name
          register_cmap(name=nam1, cmap=makemap(nam1, cm1, 256), lut=256)
          register_cmap(name=nam2, cmap=makemap(nam2, cm2, 256), lut=256)
  
      return ('stdgamma', 'red', 'green', 'blue', 'red_heat', 'green_heat',
              'blue_heat', 'magenta', 'yellow', 'cyan')
docs: registers custom color maps