diff --git a/infra/README.recipes.md b/infra/README.recipes.md
index c2737de..20e5a6b 100644
--- a/infra/README.recipes.md
+++ b/infra/README.recipes.md
@@ -18,7 +18,7 @@
 
 [DEPS](/infra/recipe_modules/macos_sdk/__init__.py#7): [recipe\_engine/cipd][recipe_engine/recipe_modules/cipd], [recipe\_engine/context][recipe_engine/recipe_modules/context], [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/platform][recipe_engine/recipe_modules/platform], [recipe\_engine/step][recipe_engine/recipe_modules/step]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 The `macos_sdk` module provides safe functions to access a semi-hermetic
 XCode installation.
@@ -68,7 +68,7 @@
 
 [DEPS](/infra/recipe_modules/target/__init__.py#7): [recipe\_engine/platform][recipe_engine/recipe_modules/platform]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 #### **class [TargetApi](/infra/recipe_modules/target/api.py#82)([RecipeApi][recipe_engine/wkt/RecipeApi]):**
 
@@ -77,7 +77,7 @@
 
 [DEPS](/infra/recipe_modules/windows_sdk/__init__.py#7): [recipe\_engine/cipd][recipe_engine/recipe_modules/cipd], [recipe\_engine/context][recipe_engine/recipe_modules/context], [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/platform][recipe_engine/recipe_modules/platform], [recipe\_engine/step][recipe_engine/recipe_modules/step]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 #### **class [WindowsSDKApi](/infra/recipe_modules/windows_sdk/api.py#10)([RecipeApi][recipe_engine/wkt/RecipeApi]):**
 
@@ -97,7 +97,7 @@
 
 [DEPS](/infra/recipes/gn.py#10): [macos\_sdk](#recipe_modules-macos_sdk), [target](#recipe_modules-target), [windows\_sdk](#recipe_modules-windows_sdk), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/cipd][recipe_engine/recipe_modules/cipd], [recipe\_engine/context][recipe_engine/recipe_modules/context], [recipe\_engine/file][recipe_engine/recipe_modules/file], [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/platform][recipe_engine/recipe_modules/platform], [recipe\_engine/properties][recipe_engine/recipe_modules/properties], [recipe\_engine/python][recipe_engine/recipe_modules/python], [recipe\_engine/raw\_io][recipe_engine/recipe_modules/raw_io], [recipe\_engine/step][recipe_engine/recipe_modules/step]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 Recipe for building GN.
 
@@ -106,21 +106,21 @@
 
 [DEPS](/infra/recipe_modules/macos_sdk/examples/full.py#7): [macos\_sdk](#recipe_modules-macos_sdk), [recipe\_engine/platform][recipe_engine/recipe_modules/platform], [recipe\_engine/properties][recipe_engine/recipe_modules/properties], [recipe\_engine/step][recipe_engine/recipe_modules/step]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 &mdash; **def [RunSteps](/infra/recipe_modules/macos_sdk/examples/full.py#15)(api):**
 ### *recipes* / [target:examples/full](/infra/recipe_modules/target/examples/full.py)
 
 [DEPS](/infra/recipe_modules/target/examples/full.py#7): [target](#recipe_modules-target), [recipe\_engine/platform][recipe_engine/recipe_modules/platform], [recipe\_engine/properties][recipe_engine/recipe_modules/properties], [recipe\_engine/step][recipe_engine/recipe_modules/step]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 &mdash; **def [RunSteps](/infra/recipe_modules/target/examples/full.py#15)(api):**
 ### *recipes* / [windows\_sdk:examples/full](/infra/recipe_modules/windows_sdk/examples/full.py)
 
 [DEPS](/infra/recipe_modules/windows_sdk/examples/full.py#7): [windows\_sdk](#recipe_modules-windows_sdk), [recipe\_engine/platform][recipe_engine/recipe_modules/platform], [recipe\_engine/properties][recipe_engine/recipe_modules/properties], [recipe\_engine/step][recipe_engine/recipe_modules/step]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 &mdash; **def [RunSteps](/infra/recipe_modules/windows_sdk/examples/full.py#15)(api):**
 
diff --git a/infra/recipe_modules/macos_sdk/__init__.py b/infra/recipe_modules/macos_sdk/__init__.py
index 550f433..44a4456 100644
--- a/infra/recipe_modules/macos_sdk/__init__.py
+++ b/infra/recipe_modules/macos_sdk/__init__.py
@@ -2,7 +2,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-PYTHON_VERSION_COMPATIBILITY = 'PY2+3'
+PYTHON_VERSION_COMPATIBILITY = 'PY3'
 
 DEPS = [
     'recipe_engine/cipd',
diff --git a/infra/recipe_modules/macos_sdk/examples/full.py b/infra/recipe_modules/macos_sdk/examples/full.py
index 242e3c5..29014fc 100644
--- a/infra/recipe_modules/macos_sdk/examples/full.py
+++ b/infra/recipe_modules/macos_sdk/examples/full.py
@@ -2,7 +2,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-PYTHON_VERSION_COMPATIBILITY = 'PY2+3'
+PYTHON_VERSION_COMPATIBILITY = 'PY3'
 
 DEPS = [
     'macos_sdk',
diff --git a/infra/recipe_modules/target/__init__.py b/infra/recipe_modules/target/__init__.py
index a4f37ae..e85b812 100644
--- a/infra/recipe_modules/target/__init__.py
+++ b/infra/recipe_modules/target/__init__.py
@@ -2,7 +2,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-PYTHON_VERSION_COMPATIBILITY = 'PY2+3'
+PYTHON_VERSION_COMPATIBILITY = 'PY3'
 
 DEPS = [
     'recipe_engine/platform',
diff --git a/infra/recipe_modules/target/examples/full.py b/infra/recipe_modules/target/examples/full.py
index 0a2090a..68af2ec 100644
--- a/infra/recipe_modules/target/examples/full.py
+++ b/infra/recipe_modules/target/examples/full.py
@@ -2,7 +2,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-PYTHON_VERSION_COMPATIBILITY = 'PY2+3'
+PYTHON_VERSION_COMPATIBILITY = 'PY3'
 
 DEPS = [
     'target',
diff --git a/infra/recipe_modules/windows_sdk/__init__.py b/infra/recipe_modules/windows_sdk/__init__.py
index 51b8492..031697b 100644
--- a/infra/recipe_modules/windows_sdk/__init__.py
+++ b/infra/recipe_modules/windows_sdk/__init__.py
@@ -2,7 +2,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-PYTHON_VERSION_COMPATIBILITY = 'PY2+3'
+PYTHON_VERSION_COMPATIBILITY = 'PY3'
 
 DEPS = [
     'recipe_engine/cipd',
diff --git a/infra/recipe_modules/windows_sdk/examples/full.py b/infra/recipe_modules/windows_sdk/examples/full.py
index 029e997..687f2e7 100644
--- a/infra/recipe_modules/windows_sdk/examples/full.py
+++ b/infra/recipe_modules/windows_sdk/examples/full.py
@@ -2,7 +2,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-PYTHON_VERSION_COMPATIBILITY = 'PY2+3'
+PYTHON_VERSION_COMPATIBILITY = 'PY3'
 
 DEPS = [
     'windows_sdk',
diff --git a/infra/recipes/gn.py b/infra/recipes/gn.py
index 4f1ea3d..bfbc4f7 100644
--- a/infra/recipes/gn.py
+++ b/infra/recipes/gn.py
@@ -5,7 +5,7 @@
 
 from recipe_engine.recipe_api import Property
 
-PYTHON_VERSION_COMPATIBILITY = 'PY2+3'
+PYTHON_VERSION_COMPATIBILITY = 'PY3'
 
 DEPS = [
     'recipe_engine/buildbucket',