Refactor fixture loading to use dictionary instead of function.

Replaced the `fixtures()` function with a dictionary object for improved readability and simplicity. Updated the related call to access the dictionary directly, eliminating unnecessary function wrapping.

Author: febus982

src/alembic/env.py

@@ -203,7 +203,7 @@ def _add_fixture_data_to_session(
         Returns:
             None
         """
-        session.add_all(fixture_module.fixtures().get(bind_name, []))
+        session.add_all(fixture_module.fixtures.get(bind_name, []))
         session.add(
             fixture_migration_models[bind_name](
                 bind=bind_name,

src/alembic/fixtures/books_example.py

@@ -3,24 +3,21 @@
 
 "BIND_NAME": "LIST_OF_FACTORIES"
 """
-
-from typing import Dict, List
-
 from factory import Factory
 
 from domains.books._models import BookModel
 
 
-def fixtures() -> Dict[str, List]:
-    class BookFactory(Factory):
-        class Meta:
-            model = BookModel
+class BookFactory(Factory):
+    class Meta:
+        model = BookModel
+
 
-    return {
-        "default": [
-            BookFactory(
-                title="The Shining",
-                author_name="Stephen King",
-            ),
-        ],
-    }
+fixtures = {
+    "default": [
+        BookFactory(
+            title="The Shining",
+            author_name="Stephen King",
+        ),
+    ],
+}