new_contents: from pyplaybulb.playbulb import Playbulb
  
  EFFECT_FLASH = '00'
  EFFECT_PULSE = '01'
  EFFECT_RAINBOW = '02'
  EFFECT_RAINBOW_FADE = '03'
  
  class Rainbow(Playbulb):
      hexa_set_colour = '0x001b'
      hexa_effect = '0x0019'
      hexa_get_colour = '0x0019'
  
      def set_colour(self, colour):
          self.connection.char_write(self.hexa_set_colour, colour)
  
      def get_colour(self):
          return self.connection.char_read(self.hexa_get_colour)
  
      def set_effect(self, effect_type, color, speed):
          self.connection.char_write(self.hexa_effect, color+effect_type+'00'+speed+'00')
subject: Create child class for Rainbow bulb