diff --git a/build/copy_info_plist.py b/build/copy_info_plist.py
index a87e1a8c98867..031975b37a8b4 100644
--- a/build/copy_info_plist.py
+++ b/build/copy_info_plist.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/build/dart/tools/dart_package_name.py b/build/dart/tools/dart_package_name.py
index 255ef5be7a13a..db8c9e93193ed 100755
--- a/build/dart/tools/dart_package_name.py
+++ b/build/dart/tools/dart_package_name.py
@@ -1,4 +1,5 @@
-#!/usr/bin/python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/build/dart/tools/dart_pkg.py b/build/dart/tools/dart_pkg.py
index 18d2e6951faf8..15c29cd7bace9 100755
--- a/build/dart/tools/dart_pkg.py
+++ b/build/dart/tools/dart_pkg.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/build/generate_coverage.py b/build/generate_coverage.py
index bf675eca09c93..ae7099f47a3fe 100755
--- a/build/generate_coverage.py
+++ b/build/generate_coverage.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/build/git_revision.py b/build/git_revision.py
index 5ee807c3abad5..778d7e70c7d60 100755
--- a/build/git_revision.py
+++ b/build/git_revision.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/build/zip.py b/build/zip.py
index b257a7ad3c53c..0bcbc02fc9006 100755
--- a/build/zip.py
+++ b/build/zip.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/ci/firebase_testlab.py b/ci/firebase_testlab.py
index 7aef50c37918b..effd543819ecd 100755
--- a/ci/firebase_testlab.py
+++ b/ci/firebase_testlab.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/shell/platform/fuchsia/flutter/build/asset_package.py b/shell/platform/fuchsia/flutter/build/asset_package.py
index 90c98fdd2f085..5ec916f5ff027 100755
--- a/shell/platform/fuchsia/flutter/build/asset_package.py
+++ b/shell/platform/fuchsia/flutter/build/asset_package.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/shell/platform/fuchsia/flutter/build/gen_debug_wrapper_main.py b/shell/platform/fuchsia/flutter/build/gen_debug_wrapper_main.py
index c16a6feca7497..d5811d5cddb05 100755
--- a/shell/platform/fuchsia/flutter/build/gen_debug_wrapper_main.py
+++ b/shell/platform/fuchsia/flutter/build/gen_debug_wrapper_main.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/sky/tools/create_ios_framework.py b/sky/tools/create_ios_framework.py
index 6ceaa658f3aa0..67092cac3b6e9 100755
--- a/sky/tools/create_ios_framework.py
+++ b/sky/tools/create_ios_framework.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/sky/tools/create_macos_gen_snapshots.py b/sky/tools/create_macos_gen_snapshots.py
index af833076fec81..301f91cf28a8e 100755
--- a/sky/tools/create_macos_gen_snapshots.py
+++ b/sky/tools/create_macos_gen_snapshots.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/sky/tools/create_xcframework.py b/sky/tools/create_xcframework.py
index 0bdc952e61798..9bd0609457dbe 100755
--- a/sky/tools/create_xcframework.py
+++ b/sky/tools/create_xcframework.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/sky/tools/dist_dart_pkg.py b/sky/tools/dist_dart_pkg.py
index af8bd1dbb201d..2a01a571e3ae2 100755
--- a/sky/tools/dist_dart_pkg.py
+++ b/sky/tools/dist_dart_pkg.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/sky/tools/flutter_gdb b/sky/tools/flutter_gdb
index 0d2fa2adb8601..273952f415f78 100755
--- a/sky/tools/flutter_gdb
+++ b/sky/tools/flutter_gdb
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/sky/tools/install_framework_headers.py b/sky/tools/install_framework_headers.py
index a746ff90b0e7e..1defe100b1ea9 100755
--- a/sky/tools/install_framework_headers.py
+++ b/sky/tools/install_framework_headers.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/sky/tools/objcopy.py b/sky/tools/objcopy.py
index b8da36d43b8e3..ed2256bc5f209 100755
--- a/sky/tools/objcopy.py
+++ b/sky/tools/objcopy.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/sky/tools/roll/patch.py b/sky/tools/roll/patch.py
index f08b610e31601..f7242b4d92489 100755
--- a/sky/tools/roll/patch.py
+++ b/sky/tools/roll/patch.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/sky/tools/roll/roll.py b/sky/tools/roll/roll.py
index c4d322cb9cebb..b526c6b7c7318 100755
--- a/sky/tools/roll/roll.py
+++ b/sky/tools/roll/roll.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/sky/tools/roll/utils.py b/sky/tools/roll/utils.py
index c14732e34d12d..c5008eec30b33 100755
--- a/sky/tools/roll/utils.py
+++ b/sky/tools/roll/utils.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/testing/rules/run_gradle.py b/testing/rules/run_gradle.py
index 41bb007ea6cc9..cdde9a818e3a4 100644
--- a/testing/rules/run_gradle.py
+++ b/testing/rules/run_gradle.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/testing/run_tests.py b/testing/run_tests.py
index 50eea3b983f7a..5881e161b1d2d 100755
--- a/testing/run_tests.py
+++ b/testing/run_tests.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/tools/android_illegal_imports.py b/tools/android_illegal_imports.py
index e07573f141f92..6c292bea12401 100644
--- a/tools/android_illegal_imports.py
+++ b/tools/android_illegal_imports.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/tools/androidx/generate_pom_file.py b/tools/androidx/generate_pom_file.py
index b2cd3deac37de..10fe63338c739 100644
--- a/tools/androidx/generate_pom_file.py
+++ b/tools/androidx/generate_pom_file.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2019 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/tools/dia_dll.py b/tools/dia_dll.py
index 9366349878a9b..010ed4f1eeb2c 100644
--- a/tools/dia_dll.py
+++ b/tools/dia_dll.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/tools/font-subset/test.py b/tools/font-subset/test.py
index d97aa4f9f08c4..977dec352be44 100755
--- a/tools/font-subset/test.py
+++ b/tools/font-subset/test.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/tools/fuchsia/build_fuchsia_artifacts.py b/tools/fuchsia/build_fuchsia_artifacts.py
index a954230bc4c27..861b6eef819d0 100755
--- a/tools/fuchsia/build_fuchsia_artifacts.py
+++ b/tools/fuchsia/build_fuchsia_artifacts.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/tools/fuchsia/compile_cml.py b/tools/fuchsia/compile_cml.py
index 36acd818a43a8..ae058d2f53946 100755
--- a/tools/fuchsia/compile_cml.py
+++ b/tools/fuchsia/compile_cml.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/tools/fuchsia/copy_debug_symbols.py b/tools/fuchsia/copy_debug_symbols.py
index 4d4cdaef686ca..cc415eb59d420 100755
--- a/tools/fuchsia/copy_debug_symbols.py
+++ b/tools/fuchsia/copy_debug_symbols.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/tools/fuchsia/copy_path.py b/tools/fuchsia/copy_path.py
index 1dd4693237754..335c262ce3dee 100755
--- a/tools/fuchsia/copy_path.py
+++ b/tools/fuchsia/copy_path.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/tools/fuchsia/gather_flutter_runner_artifacts.py b/tools/fuchsia/gather_flutter_runner_artifacts.py
index b337deeaddfd2..e2d67ab8becf6 100755
--- a/tools/fuchsia/gather_flutter_runner_artifacts.py
+++ b/tools/fuchsia/gather_flutter_runner_artifacts.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/tools/fuchsia/gen_package.py b/tools/fuchsia/gen_package.py
index 873356f7c67fd..c9bd85b74aadb 100755
--- a/tools/fuchsia/gen_package.py
+++ b/tools/fuchsia/gen_package.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/tools/fuchsia/gen_repo.py b/tools/fuchsia/gen_repo.py
index 84a72603ce225..604fe33cb2367 100755
--- a/tools/fuchsia/gen_repo.py
+++ b/tools/fuchsia/gen_repo.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/tools/fuchsia/interpolate_test_suite.py b/tools/fuchsia/interpolate_test_suite.py
index 0e484ded024b5..3e61f6520fb38 100755
--- a/tools/fuchsia/interpolate_test_suite.py
+++ b/tools/fuchsia/interpolate_test_suite.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/tools/fuchsia/make_build_info.py b/tools/fuchsia/make_build_info.py
index 4e79f8512bedd..d4565702a199c 100644
--- a/tools/fuchsia/make_build_info.py
+++ b/tools/fuchsia/make_build_info.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/tools/fuchsia/merge_and_upload_debug_symbols.py b/tools/fuchsia/merge_and_upload_debug_symbols.py
index 6b5786d2079b2..964358671e25f 100755
--- a/tools/fuchsia/merge_and_upload_debug_symbols.py
+++ b/tools/fuchsia/merge_and_upload_debug_symbols.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/tools/fuchsia/parse_manifest.py b/tools/fuchsia/parse_manifest.py
index bb7e4917e38eb..3863e6bae3199 100755
--- a/tools/fuchsia/parse_manifest.py
+++ b/tools/fuchsia/parse_manifest.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
diff --git a/tools/gen_android_buildconfig.py b/tools/gen_android_buildconfig.py
index f54c8723e914c..485d8f99987af 100644
--- a/tools/gen_android_buildconfig.py
+++ b/tools/gen_android_buildconfig.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/tools/gen_javadoc.py b/tools/gen_javadoc.py
index f19d2dda40094..b91096f79e3e4 100755
--- a/tools/gen_javadoc.py
+++ b/tools/gen_javadoc.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/tools/licenses/lib/main.dart b/tools/licenses/lib/main.dart
index 2122f20b9e56c..3adbbf6a36163 100644
--- a/tools/licenses/lib/main.dart
+++ b/tools/licenses/lib/main.dart
@@ -77,7 +77,7 @@ class _RepositorySourceFile extends _RepositoryLicensedFile {
 
   fs.TextFile get ioTextFile => super.io as fs.TextFile;
 
-  static final RegExp _hashBangPattern = RegExp(r'^#! *(?:/bin/sh|/bin/bash|/usr/bin/env +(?:python|bash))\b');
+  static final RegExp _hashBangPattern = RegExp(r'^#! *(?:/bin/sh|/bin/bash|/usr/bin/env +(?:python|python3|bash))\b');
 
   @override
   bool get isShellScript {