diff --git a/CMakeLists.txt b/CMakeLists.txt
index b190c15..6aa9963 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -75,7 +75,7 @@ endif()
 if(BUILD_PYTHON)
     set(SIP_EXTRA_FILES_DEPEND python/Types.sip python/MeshData.sip python/SceneNode.sip python/Scene.sip)
     #set(SIP_EXTRA_SOURCE_FILES python/Types.cpp)
-    set(SIP_EXTRA_OPTIONS -g) # -g means always release the GIL before calling C++ methods.
+    set(SIP_EXTRA_OPTIONS -g -n PyQt5.sip) # -g means always release the GIL before calling C++ methods.
     add_sip_python_module(Savitar python/ThreeMFParser.sip Savitar)
 endif()