class User(AbstractUser):
    balance = models.DecimalField(max_digits=7, decimal_places=2, blank=True, null=True)



class WatchList(models.Model):
    user = models.ForeignKey(User, blank=True, null=True, on_delete=models.SET_NULL)
    item = models.ForeignKey(Item, blank=True, null=True, on_delete=models.SET_NULL)

    class Meta:
        unique_together = ('user', 'item')

class UserSerializer(serializers.ModelSerializer):
    date_joined = serializers.ReadOnlyField()

    class Meta:
        model = User
        fields = ('id', 'email', 'first_name', 'last_name',
                  'date_joined', 'password')
        extra_kwargs = {'password': {'write_only': True}}