diff --git a/llvm/utils/chunk-print-before-all.py b/llvm/utils/chunk-print-before-all.py
--- a/llvm/utils/chunk-print-before-all.py
+++ b/llvm/utils/chunk-print-before-all.py
@@ -7,6 +7,7 @@
 # chunk. Files are written to current working directory.
 
 import sys
+import re
 
 chunk_id = 0