diff --git a/scripts/4.1_data_src_extract_faces_S3FD.sh b/scripts/4.1_data_src_extract_faces_S3FD.sh
index 52226d8..8a906fb 100755
--- a/scripts/4.1_data_src_extract_faces_S3FD.sh
+++ b/scripts/4.1_data_src_extract_faces_S3FD.sh
@@ -2,7 +2,7 @@
 cd "$(dirname $0)/.."
 source scripts/env.sh
 
-python "$DFL_MAIN" extract \
+$DFL_PYTHON "$DFL_MAIN" extract \
   --input-dir "$WORKSPACE/data_src" \
   --output-dir "$WORKSPACE/data_src/aligned" \
   --detector s3fd