Index: purge.py
==================================================================
--- purge.py
+++ purge.py
@@ -27,11 +27,11 @@
 
 
 def main ():
     "purge cruft and other files"
     print("Python: " + sys.version)
-    if sys.version < "3.7":
+    if sys.version_info < (3, 7):
         print("Python 3.7+ required")
         return
 
     xParser = argparse.ArgumentParser()
     xParser.add_argument("-b", "--build", help="purge _build", action="store_true")