Removed IPAddressField per deprecation timeline; refs #20439.

tests/invalid_models_tests/test_deprecated_fields.py

@@ -0,0 +1,22 @@
+from django.core import checks
+from django.db import models
+
+from .base import IsolatedModelsTestCase
+
+
+class DeprecatedFieldssTests(IsolatedModelsTestCase):
+    def test_IPAddressField_deprecated(self):
+        class IPAddressModel(models.Model):
+            ip = models.IPAddressField()
+
+        model = IPAddressModel()
+        self.assertEqual(
+            model.check(),
+            [checks.Error(
+                'IPAddressField has been removed except for support in '
+                'historical migrations.',
+                hint='Use GenericIPAddressField instead.',
+                obj=IPAddressModel._meta.get_field('ip'),
+                id='fields.E900',
+            )],
+        )