diff --git a/book/features/pull_request_build.md b/book/features/pull_request_build.md
index 649b40c..63f4ffd 100644
--- a/book/features/pull_request_build.md
+++ b/book/features/pull_request_build.md
@@ -62,7 +62,6 @@ build:
 python:
   install:
     - requirements: requirements.txt
-    - requirements: standard-imghdr
 
 sphinx:
   builder: html