Have you conducted modular testing of an API implemented with Django?

Yes, unit testing of APIs in Django is usually performed using the built-in test client django.test.Client or with APIClient from Django REST Framework. This allows sending requests to the API and checking responses without starting the server.

A simple example of a test for an API in Django REST Framework:

from rest_framework.test import APITestCase
from django.urls import reverse

class MyAPITest(APITestCase):
    def test_get_items(self):
        url = reverse('items-list')  # route name
        response = self.client.get(url)
        self.assertEqual(response.status_code, 200)
        self.assertIsInstance(response.data, list)

This approach allows isolating the logic of request processing, serialization, and returned data.