Solution

car/migrations/0001_initial.py

@@ -0,0 +1,41 @@
+# Generated by Django 4.1 on 2026-04-15 20:24
+
+import django.core.validators
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = []
+
+    operations = [
+        migrations.CreateModel(
+            name="Car",
+            fields=[
+                (
+                    "id",
+                    models.BigAutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                ("manufacturer", models.CharField(max_length=64)),
+                ("model", models.CharField(max_length=64)),
+                (
+                    "horse_powers",
+                    models.PositiveSmallIntegerField(
+                        validators=[
+                            django.core.validators.MaxValueValidator(1914),
+                            django.core.validators.MinValueValidator(1),
+                        ]
+                    ),
+                ),
+                ("is_broken", models.BooleanField()),
+                ("problem_description", models.TextField(blank=True, null=True)),
+            ],
+        ),
+    ]

car/serializers.py

@@ -1,5 +1,54 @@
+from django.core.validators import MinValueValidator, MaxValueValidator
 from rest_framework import serializers
+from car.models import Car
 
 
 class CarSerializer(serializers.Serializer):
-    pass
+    id = serializers.IntegerField(read_only=True)
+    manufacturer = serializers.CharField(required=True, max_length=64)
+    model = serializers.CharField(required=True, max_length=64)
+    horse_powers = serializers.IntegerField(
+        required=True,
+        validators=[
+            MinValueValidator(
+                1,
+                message="Min horse_power must be equal or greater than 1."
+            ),
+            MaxValueValidator(
+                1914,
+                message="Max horse_power must be equal or less than 1914."
+            ),
+        ],
+    )
+    is_broken = serializers.BooleanField()
+    problem_description = serializers.CharField(
+        allow_null=True,
+        required=False
+    )
+
+    def create(self, validated_data):
+        return Car.objects.create(**validated_data)
+
+    def update(self, instance, validated_data):
+        instance.manufacturer = validated_data.get(
+            "manufacturer", instance.manufacturer
+        )
+        instance.model = validated_data.get("model", instance.model)
+        instance.horse_power = validated_data.get(
+            "horse_power",
+            instance.horse_power
+        )
+        instance.is_broken = validated_data.get(
+            "is_broken",
+            instance.is_broken
+        )
+        instance.problem_description = validated_data.get(
+            "problem_description",
+            instance.problem_description
+        )
+        instance.save()
+        return instance
+
+    class Meta:
+        model = Car
+        fields = "__all__"

car/tests/tests.py

@@ -58,8 +58,14 @@ def test_horse_powers(self):
 
     def test_fields_max_length(self):
         items = [
-            ("manufacturer", "Extremely long test manufacturer Extremely long test manufacturer"),
-            ("model", "Extremely long test model Extremely long test model Extremely long test model")
+            (
+                "manufacturer",
+                "Extremely long test manufacturer Extremely long test manufacturer",
+            ),
+            (
+                "model",
+                "Extremely long test model Extremely long test model Extremely long test model",
+            ),
         ]
 
         for item in items:
@@ -91,14 +97,18 @@ def setUp(self) -> None:
 
     def test_serialize_car(self):
         car = Car(**self.payload)
-        result = '{"id":1,"manufacturer":"Audi","model":"A4","horse_powers":200,' \
-                 '"is_broken":true,"problem_description":"test description"}'
+        result = (
+            '{"id":1,"manufacturer":"Audi","model":"A4","horse_powers":200,'
+            '"is_broken":true,"problem_description":"test description"}'
+        )
 
         self.assertEqual(serialize_car_object(car=car), bytes(result, "utf-8"))
 
     def test_deserialize_car(self):
-        json = b'{"id":1,"manufacturer":"Audi","model":"A4",' \
-                    b'"horse_powers":200,"is_broken":true,"problem_description":"test description"}'
+        json = (
+            b'{"id":1,"manufacturer":"Audi","model":"A4",'
+            b'"horse_powers":200,"is_broken":true,"problem_description":"test description"}'
+        )
 
         car = deserialize_car_object(json)
 

car_service/urls.py

@@ -13,6 +13,7 @@
     1. Import the include() function: from django.urls import include, path
     2. Add a URL to urlpatterns:  path('blog/', include('blog.urls'))
 """
+
 from django.contrib import admin
 from django.urls import path
 

main.py

@@ -1,9 +1,21 @@
+import io
+from rest_framework.renderers import JSONRenderer
+from rest_framework.parsers import JSONParser
 from car.models import Car
+from car.serializers import CarSerializer
 
 
 def serialize_car_object(car: Car) -> bytes:
-    pass
+    serializer = CarSerializer(car)
+    return JSONRenderer().render(serializer.data)
 
 
 def deserialize_car_object(json: bytes) -> Car:
-    pass
+    stream = io.BytesIO(json)
+    data = JSONParser().parse(stream)
+
+    serializer = CarSerializer(data=data)
+
+    serializer.is_valid(raise_exception=True)
+
+    return serializer.save()