diff --git a/Utilities/build-script-helper.py b/Utilities/build-script-helper.py
index 6e574056..eb8ef08a 100755
--- a/Utilities/build-script-helper.py
+++ b/Utilities/build-script-helper.py
@@ -1,6 +1,4 @@
-#!/usr/bin/env python
-
-from __future__ import print_function
+#!/usr/bin/env python3
 
 import argparse
 import os
@@ -93,7 +91,10 @@ def add_common_args(parser):
     parser.add_argument('--sanitize-all', action='store_true', help='build using every available sanitizer in sub-directories of build path')
     parser.add_argument('--verbose', '-v', action='store_true', help='enable verbose output')
 
-  subparsers = parser.add_subparsers(title='subcommands', dest='action', metavar='action')
+  if sys.version_info >= (3,7,0):
+    subparsers = parser.add_subparsers(title='subcommands', dest='action', required=True, metavar='action')
+  else:
+    subparsers = parser.add_subparsers(title='subcommands', dest='action', metavar='action')
   build_parser = subparsers.add_parser('build', help='build the package')
   add_common_args(build_parser)
 
diff --git a/Utilities/import-llvm b/Utilities/import-llvm
index 62b9e768..fe8ce7f3 100755
--- a/Utilities/import-llvm
+++ b/Utilities/import-llvm
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 # This is a helper script for importing the things we use from LLVM.
 #