diff --git a/databases/backends/postgres.py b/databases/backends/postgres.py
index 61dee448..65023ccc 100644
--- a/databases/backends/postgres.py
+++ b/databases/backends/postgres.py
@@ -44,7 +44,7 @@ def _get_dialect(self) -> Dialect:
     def _get_connection_kwargs(self) -> dict:
         url_options = self._database_url.options
 
-        kwargs = {}
+        kwargs = {}  # type: typing.Dict[str, typing.Any]
         min_size = url_options.get("min_size")
         max_size = url_options.get("max_size")
         ssl = url_options.get("ssl")