halp, why doesn't this work? getting http 404

modified:   app.py
	new file:   openapi.yaml
	modified:   requirements.txt

app.py

@@ -524,9 +524,9 @@ def download_database_view(request):
     download_filename = sanitize_filename_for_http_header(f"user_{user.id}.db")
 
     response = Response(body=data, content_type="application/octet-stream")
-    response.headers[
-        "Content-Disposition"
-    ] = f'attachment; filename="{download_filename}"'
+    response.headers["Content-Disposition"] = (
+        f'attachment; filename="{download_filename}"'
+    )
     return response
 
 
@@ -1005,7 +1005,19 @@ def main(global_config=None, **settings):
     config.add_jinja2_renderer(".j2")
     config.add_jinja2_search_path("templates", name=".j2")
 
-    # The Jinja2 filters are added via the event subscriber above
+    # Add settings for pyramid_openapi3
+    config.add_settings(
+        {
+            "pyramid_openapi3.spec": os.path.join(APP_DIR, "openapi.yaml"),
+            "pyramid_openapi3.enable_request_validation": True,
+            "pyramid_openapi3.enable_response_validation": False,
+            "pyramid_openapi3.route": "/openapi.yaml",
+            "pyramid_openapi3.ui_route": "/docs/",
+        }
+    )
+
+    # Include pyramid_openapi3
+    config.include("pyramid_openapi3")
 
     # Set up SQLAlchemy
     engine = create_engine(