diff --git a/docs/source/conf.py b/docs/source/conf.py
index 6037c81a0b7..7c8ae21cb7b 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -45,7 +45,7 @@
 
 if os.getenv("READTHEDOCS"):
     # Use rtds_action if we are building on read the docs and have a github token env var
-    if os.getenv["GITHUB_TOKEN"]:
+    if os.getenv("GITHUB_TOKEN"):
         extensions += ['rtds_action']
 
         # The name of your GitHub repository