diff --git a/cwltest/__init__.py b/cwltest/__init__.py
index a7a498c..9eda222 100755
--- a/cwltest/__init__.py
+++ b/cwltest/__init__.py
@@ -32,7 +32,7 @@
 UNSUPPORTED_FEATURE = 33
 DEFAULT_TIMEOUT = 900  # 15 minutes
 
-if sys.version_info.major < 3:
+if sys.version_info < (3, 0):
     import subprocess32 as subprocess
 else:
     import subprocess