diff --git a/altair/vegalite/v5/display.py b/altair/vegalite/v5/display.py
index 7b23e0710..da7db78e5 100644
--- a/altair/vegalite/v5/display.py
+++ b/altair/vegalite/v5/display.py
@@ -86,7 +86,7 @@ def svg_renderer(spec: dict, **metadata) -> Dict[str, str]:
     )
 
 
-def render_jupyter(spec):
+def jupyter_renderer(spec: dict):
     """Render chart using the JupyterChart Jupyter Widget"""
     from altair import Chart, JupyterChart
 
@@ -112,7 +112,7 @@ def render_jupyter(spec):
 renderers.register("json", json_renderer)
 renderers.register("png", png_renderer)
 renderers.register("svg", svg_renderer)
-renderers.register("jupyter", render_jupyter)
+renderers.register("jupyter", jupyter_renderer)
 renderers.enable("default")