diff --git a/CMakeLists.txt b/CMakeLists.txt
index a1eea7b..00fbaf3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -18,7 +18,7 @@ ELSE ()
     MESSAGE (FATAL_ERROR "Invalid PYTHON_DESIRED value: " ${PYTHON_DESIRED})
 ENDIF()

-EXECUTE_PROCESS(COMMAND ${PYTHON_EXECUTABLE} -c "from sys import stdout; from sysconfig import get_path; stdout.write(get_path('purelib'))" OUTPUT_VARIABLE PYTHON_INSTALL_DIR)
+SET(PYTHON_INSTALL_DIR "@PYTHON_INSTALL_DIR@")
 MESSAGE(STATUS "Python install dir is ${PYTHON_INSTALL_DIR}")

 SET (SYSCONFDIR /etc)