diff --git a/main.py b/main.py
index ba4dffe..3fa0fa7 100644
--- a/main.py
+++ b/main.py
@@ -115,11 +115,12 @@ def get_kytos_topology():
         return topology
 
     @listen_to("kytos/topology.topology_loaded")
-    def on_topology_loaded(self, event: KytosEvent):
+    def on_topology_loaded(self, _event: KytosEvent):
         """Handler for on topology_loaded."""
         self.handler_on_topology_loaded()
 
     def handler_on_topology_loaded(self):
+        """Hnalder on_topology_loaded."""
         self.load_kytos_topology()
 
     @listen_to("kytos/topology.updated")
diff --git a/tests/unit/test_main.py b/tests/unit/test_main.py
index 844a8d5..1b928a0 100644
--- a/tests/unit/test_main.py
+++ b/tests/unit/test_main.py
@@ -115,6 +115,15 @@ async def test_create_l2vpn(self, requests_mock):
         assert response.status_code == 201
         assert response.json() == {"service_id": "a123"}
 
+    def test_handler_on_topology_loaded(self):
+        """Test handler_on_topology_loaded."""
+        self.napp.get_kytos_topology = MagicMock()
+        some_topo = {"switches": {"dpid1": {}}, "links": {"link1": {}}}
+        self.napp.get_kytos_topology.return_value = some_topo
+        self.napp.convert_topology_v2 = MagicMock()
+        self.napp.handler_on_topology_loaded()
+        assert self.napp._topo_dict == some_topo
+
     @patch("requests.post")
     @patch("requests.patch")
     async def test_update_l2vpn(self, req_patch_mock, req_post_mock):