class Device(BaseDevice):
    """
    This stores Device
    """
    description = models.TextField(blank=True, null=True)
    device_group = models.ForeignKey('DeviceGroup', null=True, blank=True)
    created_on = models.DateTimeField(auto_now_add=True)
    updated_on= models.DateTimeField(auto_now=True)

class DeviceGroup(models.Model):
    name = models.CharField(max_length=250, blank=False, null=False)
    created_on = models.DateTimeField(auto_now_add=True)
    updated_on= models.DateTimeField(auto_now=True)

class DeviceSerializer(serializers.ModelSerializer):
    id = serializers.UUIDField(source='token', format='hex', read_only=True)
    io = DeviceIOSerializer(read_only=False, many=True, required=False)
    class Meta:
        model = Device
        fields = ('id', 'name', 'description', 'io', 'device_group')