diff --git a/client/pyscripts/mf_backdoor_dump.py b/client/pyscripts/mf_backdoor_dump.py
index e8836c358..897e46381 100644
--- a/client/pyscripts/mf_backdoor_dump.py
+++ b/client/pyscripts/mf_backdoor_dump.py
@@ -6,6 +6,7 @@
 
 import pm3
 import os
+import sys
 
 TOTAL_SECTORS = 16 #1k chips