diff --git a/deskew/__init__.py b/deskew/__init__.py
index f983efc4..580914a3 100644
--- a/deskew/__init__.py
+++ b/deskew/__init__.py
@@ -267,7 +267,7 @@ def fill_polar(
         limits: list[tuple[float, float]],
         half: bool = False,
     ) -> None:
-        axe.scatter(freqs.keys(), freqs.values())
+        axe.scatter(list(freqs.keys()), list(freqs.values()))
         axe.set_theta_zero_location("N")
         axe.grid(True)
         if half: