Add some comments

dungeonbattle/interfaces_test.py

@@ -5,6 +5,9 @@ from dungeonbattle.interfaces import Map
 
 class TestInterfaces(unittest.TestCase):
     def test_map(self) -> None:
+        """
+        Create a map and check that it is well parsed.
+        """
         m = Map.load_from_string(".#\n#.\n")
         self.assertEqual(m.width, 2)
         self.assertEqual(m.height, 2)