code: def flightmode_colour(self, flightmode):
          '''return colour to be used for rendering a flight mode background'''
          if flightmode not in self.flightmode_colourmap:
              self.flightmode_colourmap[flightmode] = self.next_flightmode_colour()
          return self.flightmode_colourmap[flightmodef flightmode_colour(self, flightmode):
          '''return colour to be used for rendering a flight mode background'''
          if flightmode not in self.flightmode_colourmap:
              self.flightmode_colourmap[flightmode] = self.next_flightmode_colour()
          return self.flightmode_colourmap[flightmode]
docs: return colour to be used for rendering a flight mode background