diff --git a/python-sphinx.spec b/python-sphinx.spec
index 25e3516..754ea9a 100644
--- a/python-sphinx.spec
+++ b/python-sphinx.spec
@@ -6,7 +6,7 @@
 
 # Unset -s on python shebang to allow RPM-installed sphinx to be used
 # with user-installed modules (#1903763)
-%global py3_shebang_flags %(echo %py3_shebang_flags | sed s/s//)
+%undefine _py3_shebang_s
 
 # No internet in Koji
 %bcond_with internet