diff --git a/docs/.readthedocs.yaml b/docs/.readthedocs.yaml
index 1ffe0f7d..1818faa1 100644
--- a/docs/.readthedocs.yaml
+++ b/docs/.readthedocs.yaml
@@ -3,7 +3,7 @@ version: 2
 build:
   os: ubuntu-lts-latest
   tools:
-    python: 3
+    python: '3'
 
 formats: all