diff --git a/readthedocs.yml b/readthedocs.yml
index 4940390..12484f0 100644
--- a/readthedocs.yml
+++ b/readthedocs.yml
@@ -1,10 +1,12 @@
 version: 2
 
 build:
-   image: latest
+  os: ubuntu-20.04
+  tools:
+    python: '3.9'
 
 python:
-   version: 3.7
+   version: 3.9
    install:
       - method: pip
         path: .