docs: def get_color_palette(scheme):
      """Return colors for a given scheme. Default colors are returned for an item
      if undefined in scheme.
  
      """
      color_schemes = {
          'default': {
              'frames': ['tomato', 'limegreen', 'deepskyblue'], 'background': '#ffffff',
              'color': '#616161', 'ticks': '#757575', 'start': '#ffffff', 'stop': '#909090',
              'rna': '#eaeaea', 'axis': '#e0e0e0', 'grey': '#bdbdbd'
          },
          'colorbrewer': {
              'frames': ['#fc8d62', '#66c2a5', '#8da0cb']
          },
          'rgb': {
              'frames': ['red', 'green', 'blue']
          },
          'greyorfs': {}
      }
  
      colors = {}
      for k, v in color_schemes['default'].items():
          try:
              vals = color_schemes[scheme][k]
          except KeyError:
              vals = v
          colors[k] = vals
      return colors