code: def set_all_pwm(self, on, off):
          
          self.i2c.write8(ALL_LED_ON_L, on & 0xFF)
          self.i2c.write8(ALL_LED_ON_H, on >> 8)
          self.i2c.write8(ALL_LED_OFF_L, off & 0xFF)
          self.i2c.write8(ALL_LED_OFF_H, off >> 8)
docs: Sets all PWM channels.