code: def test_invalid_text(self):
      response = self.client.post(
          self.api_url,
          data=json.dumps({"type": "classmethod"}),
          content_type="application/json",
          format="json",
      )
  
      self.assertEqual(response.status_code, 400)
      self.assertIn("text", response.json())
      self.assertEqual(
          ['The attribute "text" is required.'], response.json()["text"]
      )
  
file_path: ChatterBot/examples/django_app/tests/test_api.py
imports: import json
  from django.test import TestCase
  from django.urls import reverse
label_desc: Use image node_id 2 for calling the ApiTestCase obj's underlying member method code with example usage: obj.test_invalid_text() without return types