diff --git a/pdfminer/pdfdevice.py b/pdfminer/pdfdevice.py
index 896ca8e..0df67bd 100644
--- a/pdfminer/pdfdevice.py
+++ b/pdfminer/pdfdevice.py
@@ -1,5 +1,6 @@
 #!/usr/bin/env python
 
+import sys
 from pdfminer.utils import mult_matrix, translate_matrix, apply_matrix_norm
 from pdfminer.pdffont import PDFUnicodeNotDefined