diff --git a/infra/config/recipes.cfg b/infra/config/recipes.cfg
index 6e565cedd..9be7b1193 100644
--- a/infra/config/recipes.cfg
+++ b/infra/config/recipes.cfg
@@ -22,5 +22,6 @@
   },
   "project_id": "depot_tools",
   "recipes_path": "recipes",
+  "py3_only": true,
   "repo_name": "depot_tools"
 }
diff --git a/recipes/README.recipes.md b/recipes/README.recipes.md
index ff9600316..d67cf498a 100644
--- a/recipes/README.recipes.md
+++ b/recipes/README.recipes.md
@@ -51,7 +51,7 @@
 
 [DEPS](/recipes/recipe_modules/bot_update/__init__.py#3): [depot\_tools](#recipe_modules-depot_tools), [gclient](#recipe_modules-gclient), [gerrit](#recipe_modules-gerrit), [gitiles](#recipe_modules-gitiles), [tryserver](#recipe_modules-tryserver), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/commit\_position][recipe_engine/recipe_modules/commit_position], [recipe\_engine/context][recipe_engine/recipe_modules/context], [recipe\_engine/cq][recipe_engine/recipe_modules/cq], [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/milo][recipe_engine/recipe_modules/milo], [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/raw\_io][recipe_engine/recipe_modules/raw_io], [recipe\_engine/runtime][recipe_engine/recipe_modules/runtime], [recipe\_engine/step][recipe_engine/recipe_modules/step]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 Recipe module to ensure a checkout is consistent on a bot.
 
@@ -121,7 +121,7 @@ properties.
 
 [DEPS](/recipes/recipe_modules/depot_tools/__init__.py#7): [recipe\_engine/cipd][recipe_engine/recipe_modules/cipd], [recipe\_engine/context][recipe_engine/recipe_modules/context], [recipe\_engine/platform][recipe_engine/recipe_modules/platform], [recipe\_engine/runtime][recipe_engine/recipe_modules/runtime]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 The `depot_tools` module provides safe functions to access paths within
 the depot_tools repo.
@@ -158,7 +158,7 @@ Returns (Path): The "depot_tools" root directory.
 
 [DEPS](/recipes/recipe_modules/gclient/__init__.py#3): [git](#recipe_modules-git), [gitiles](#recipe_modules-gitiles), [tryserver](#recipe_modules-tryserver), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [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/properties][recipe_engine/recipe_modules/properties], [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
 
 #### **class [GclientApi](/recipes/recipe_modules/gclient/api.py#77)([RecipeApi][recipe_engine/wkt/RecipeApi]):**
 
@@ -242,7 +242,7 @@ revision map. This doesn't overwrite the revision if it was already set.
 
 [DEPS](/recipes/recipe_modules/gerrit/__init__.py#3): [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/raw\_io][recipe_engine/recipe_modules/raw_io], [recipe\_engine/step][recipe_engine/recipe_modules/step], [recipe\_engine/time][recipe_engine/recipe_modules/time]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 #### **class [GerritApi](/recipes/recipe_modules/gerrit/api.py#7)([RecipeApi][recipe_engine/wkt/RecipeApi]):**
 
@@ -381,7 +381,7 @@ Returns:
 
 [DEPS](/recipes/recipe_modules/git/__init__.py#3): [depot\_tools](#recipe_modules-depot_tools), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/context][recipe_engine/recipe_modules/context], [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/raw\_io][recipe_engine/recipe_modules/raw_io], [recipe\_engine/runtime][recipe_engine/recipe_modules/runtime], [recipe\_engine/step][recipe_engine/recipe_modules/step]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 #### **class [GitApi](/recipes/recipe_modules/git/api.py#19)([RecipeApi][recipe_engine/wkt/RecipeApi]):**
 
@@ -525,7 +525,7 @@ Args:
 
 [DEPS](/recipes/recipe_modules/git_cl/__init__.py#3): [recipe\_engine/context][recipe_engine/recipe_modules/context], [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
 
 #### **class [GitClApi](/recipes/recipe_modules/git_cl/api.py#9)([RecipeApi][recipe_engine/wkt/RecipeApi]):**
 
@@ -544,7 +544,7 @@ PYTHON_VERSION_COMPATIBILITY: PY2+3
 
 [DEPS](/recipes/recipe_modules/gitiles/__init__.py#7): [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/raw\_io][recipe_engine/recipe_modules/raw_io], [recipe\_engine/step][recipe_engine/recipe_modules/step], [recipe\_engine/url][recipe_engine/recipe_modules/url]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 #### **class [Gitiles](/recipes/recipe_modules/gitiles/api.py#18)([RecipeApi][recipe_engine/wkt/RecipeApi]):**
 
@@ -635,7 +635,7 @@ Generates a Gitiles repo URL. See also parse_repo_url.
 
 [DEPS](/recipes/recipe_modules/gsutil/__init__.py#5): [recipe\_engine/context][recipe_engine/recipe_modules/context], [recipe\_engine/file][recipe_engine/recipe_modules/file], [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 [GSUtilApi](/recipes/recipe_modules/gsutil/api.py#10)([RecipeApi][recipe_engine/wkt/RecipeApi]):**
 
@@ -692,7 +692,7 @@ Args:
 
 [DEPS](/recipes/recipe_modules/osx_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], [recipe\_engine/version][recipe_engine/recipe_modules/version]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 The `osx_sdk` module provides safe functions to access a semi-hermetic
 XCode installation.
@@ -756,7 +756,7 @@ Raises:
 
 [DEPS](/recipes/recipe_modules/presubmit/__init__.py#13): [bot\_update](#recipe_modules-bot_update), [depot\_tools](#recipe_modules-depot_tools), [gclient](#recipe_modules-gclient), [git](#recipe_modules-git), [tryserver](#recipe_modules-tryserver), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/context][recipe_engine/recipe_modules/context], [recipe\_engine/cq][recipe_engine/recipe_modules/cq], [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/properties][recipe_engine/recipe_modules/properties], [recipe\_engine/resultdb][recipe_engine/recipe_modules/resultdb], [recipe\_engine/step][recipe_engine/recipe_modules/step]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 #### **class [PresubmitApi](/recipes/recipe_modules/presubmit/api.py#16)([RecipeApi][recipe_engine/wkt/RecipeApi]):**
 
@@ -797,7 +797,7 @@ Returns:
 
 [DEPS](/recipes/recipe_modules/tryserver/__init__.py#7): [gerrit](#recipe_modules-gerrit), [git](#recipe_modules-git), [git\_cl](#recipe_modules-git_cl), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/context][recipe_engine/recipe_modules/context], [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/led][recipe_engine/recipe_modules/led], [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/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
 
 #### **class [TryserverApi](/recipes/recipe_modules/tryserver/api.py#27)([RecipeApi][recipe_engine/wkt/RecipeApi]):**
 
@@ -959,7 +959,7 @@ timeout.
 
 [DEPS](/recipes/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/step][recipe_engine/recipe_modules/step]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 The `windows_sdk` module provides safe functions to access a hermetic
 Microsoft Visual Studio installation which is derived from Chromium's MSVC
@@ -1002,119 +1002,119 @@ Raises:
 
 [DEPS](/recipes/recipe_modules/bot_update/examples/full.py#9): [bot\_update](#recipe_modules-bot_update), [gclient](#recipe_modules-gclient), [gerrit](#recipe_modules-gerrit), [tryserver](#recipe_modules-tryserver), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [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/runtime][recipe_engine/recipe_modules/runtime]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/bot_update/examples/full.py#27)(api):**
 ### *recipes* / [bot\_update:tests/do\_not\_retry\_patch\_failures\_in\_cq](/recipes/recipe_modules/bot_update/tests/do_not_retry_patch_failures_in_cq.py)
 
 [DEPS](/recipes/recipe_modules/bot_update/tests/do_not_retry_patch_failures_in_cq.py#9): [bot\_update](#recipe_modules-bot_update), [gclient](#recipe_modules-gclient), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/cq][recipe_engine/recipe_modules/cq], [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
 
 — **def [RunSteps](/recipes/recipe_modules/bot_update/tests/do_not_retry_patch_failures_in_cq.py#19)(api):**
 ### *recipes* / [bot\_update:tests/download\_topics](/recipes/recipe_modules/bot_update/tests/download_topics.py)
 
 [DEPS](/recipes/recipe_modules/bot_update/tests/download_topics.py#9): [bot\_update](#recipe_modules-bot_update), [gclient](#recipe_modules-gclient), [recipe\_engine/json][recipe_engine/recipe_modules/json]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/bot_update/tests/download_topics.py#16)(api):**
 ### *recipes* / [bot\_update:tests/ensure\_checkout](/recipes/recipe_modules/bot_update/tests/ensure_checkout.py)
 
 [DEPS](/recipes/recipe_modules/bot_update/tests/ensure_checkout.py#9): [bot\_update](#recipe_modules-bot_update), [gclient](#recipe_modules-gclient), [recipe\_engine/json][recipe_engine/recipe_modules/json]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/bot_update/tests/ensure_checkout.py#16)(api):**
 ### *recipes* / [depot\_tools:examples/full](/recipes/recipe_modules/depot_tools/examples/full.py)
 
 [DEPS](/recipes/recipe_modules/depot_tools/examples/full.py#7): [depot\_tools](#recipe_modules-depot_tools), [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/platform][recipe_engine/recipe_modules/platform], [recipe\_engine/runtime][recipe_engine/recipe_modules/runtime], [recipe\_engine/step][recipe_engine/recipe_modules/step]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/depot_tools/examples/full.py#16)(api):**
 ### *recipes* / [gclient:examples/full](/recipes/recipe_modules/gclient/examples/full.py)
 
 [DEPS](/recipes/recipe_modules/gclient/examples/full.py#7): [gclient](#recipe_modules-gclient), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/context][recipe_engine/recipe_modules/context], [recipe\_engine/path][recipe_engine/recipe_modules/path], [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
 
 — **def [RunSteps](/recipes/recipe_modules/gclient/examples/full.py#67)(api):**
 ### *recipes* / [gclient:tests/diff\_deps](/recipes/recipe_modules/gclient/tests/diff_deps.py)
 
 [DEPS](/recipes/recipe_modules/gclient/tests/diff_deps.py#9): [gclient](#recipe_modules-gclient), [recipe\_engine/assertions][recipe_engine/recipe_modules/assertions], [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [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/raw\_io][recipe_engine/recipe_modules/raw_io]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/gclient/tests/diff_deps.py#20)(api):**
 ### *recipes* / [gclient:tests/patch\_project](/recipes/recipe_modules/gclient/tests/patch_project.py)
 
 [DEPS](/recipes/recipe_modules/gclient/tests/patch_project.py#11): [gclient](#recipe_modules-gclient), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/properties][recipe_engine/recipe_modules/properties]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/gclient/tests/patch_project.py#20)(api):**
 ### *recipes* / [gclient:tests/sync\_failure](/recipes/recipe_modules/gclient/tests/sync_failure.py)
 
 [DEPS](/recipes/recipe_modules/gclient/tests/sync_failure.py#9): [gclient](#recipe_modules-gclient), [recipe\_engine/path][recipe_engine/recipe_modules/path]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/gclient/tests/sync_failure.py#15)(api):**
 ### *recipes* / [gerrit:examples/full](/recipes/recipe_modules/gerrit/examples/full.py)
 
 [DEPS](/recipes/recipe_modules/gerrit/examples/full.py#7): [gerrit](#recipe_modules-gerrit), [recipe\_engine/step][recipe_engine/recipe_modules/step]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/gerrit/examples/full.py#13)(api):**
 ### *recipes* / [git:examples/full](/recipes/recipe_modules/git/examples/full.py)
 
 [DEPS](/recipes/recipe_modules/git/examples/full.py#7): [git](#recipe_modules-git), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/context][recipe_engine/recipe_modules/context], [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/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
 
 — **def [RunSteps](/recipes/recipe_modules/git/examples/full.py#20)(api):**
 ### *recipes* / [git:tests/number](/recipes/recipe_modules/git/tests/number.py)
 
 [DEPS](/recipes/recipe_modules/git/tests/number.py#9): [git](#recipe_modules-git), [recipe\_engine/assertions][recipe_engine/recipe_modules/assertions], [recipe\_engine/properties][recipe_engine/recipe_modules/properties]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/git/tests/number.py#16)(api):**
 ### *recipes* / [git\_cl:examples/full](/recipes/recipe_modules/git_cl/examples/full.py)
 
 [DEPS](/recipes/recipe_modules/git_cl/examples/full.py#11): [git\_cl](#recipe_modules-git_cl), [recipe\_engine/path][recipe_engine/recipe_modules/path], [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
 
 — **def [RunSteps](/recipes/recipe_modules/git_cl/examples/full.py#19)(api):**
 ### *recipes* / [gitiles:examples/full](/recipes/recipe_modules/gitiles/examples/full.py)
 
 [DEPS](/recipes/recipe_modules/gitiles/examples/full.py#7): [gitiles](#recipe_modules-gitiles), [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/path][recipe_engine/recipe_modules/path], [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
 
 — **def [RunSteps](/recipes/recipe_modules/gitiles/examples/full.py#16)(api):**
 ### *recipes* / [gitiles:tests/parse\_repo\_url](/recipes/recipe_modules/gitiles/tests/parse_repo_url.py)
 
 [DEPS](/recipes/recipe_modules/gitiles/tests/parse_repo_url.py#7): [gitiles](#recipe_modules-gitiles), [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
 
 — **def [RunSteps](/recipes/recipe_modules/gitiles/tests/parse_repo_url.py#14)(api):**
 ### *recipes* / [gsutil:examples/custom\_boto](/recipes/recipe_modules/gsutil/examples/custom_boto.py)
 
 [DEPS](/recipes/recipe_modules/gsutil/examples/custom_boto.py#10): [gsutil](#recipe_modules-gsutil), [recipe\_engine/platform][recipe_engine/recipe_modules/platform], [recipe\_engine/properties][recipe_engine/recipe_modules/properties]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/gsutil/examples/custom_boto.py#21)(api, boto_configs):**
 ### *recipes* / [gsutil:examples/full](/recipes/recipe_modules/gsutil/examples/full.py)
 
 [DEPS](/recipes/recipe_modules/gsutil/examples/full.py#7): [gsutil](#recipe_modules-gsutil), [recipe\_engine/path][recipe_engine/recipe_modules/path]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/gsutil/examples/full.py#13)(api):**
 
@@ -1123,77 +1123,77 @@ Move things around in a loop!
 
 [DEPS](/recipes/recipe_modules/osx_sdk/examples/full.py#7): [osx\_sdk](#recipe_modules-osx_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
 
 — **def [RunSteps](/recipes/recipe_modules/osx_sdk/examples/full.py#15)(api):**
 ### *recipes* / [presubmit:examples/full](/recipes/recipe_modules/presubmit/examples/full.py)
 
 [DEPS](/recipes/recipe_modules/presubmit/examples/full.py#7): [presubmit](#recipe_modules-presubmit), [recipe\_engine/json][recipe_engine/recipe_modules/json]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/presubmit/examples/full.py#13)(api):**
 ### *recipes* / [presubmit:tests/execute](/recipes/recipe_modules/presubmit/tests/execute.py)
 
 [DEPS](/recipes/recipe_modules/presubmit/tests/execute.py#12): [gclient](#recipe_modules-gclient), [presubmit](#recipe_modules-presubmit), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/context][recipe_engine/recipe_modules/context], [recipe\_engine/cq][recipe_engine/recipe_modules/cq], [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/properties][recipe_engine/recipe_modules/properties], [recipe\_engine/runtime][recipe_engine/recipe_modules/runtime]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/presubmit/tests/execute.py#25)(api):**
 ### *recipes* / [presubmit:tests/prepare](/recipes/recipe_modules/presubmit/tests/prepare.py)
 
 [DEPS](/recipes/recipe_modules/presubmit/tests/prepare.py#11): [gclient](#recipe_modules-gclient), [presubmit](#recipe_modules-presubmit), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/context][recipe_engine/recipe_modules/context], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/properties][recipe_engine/recipe_modules/properties], [recipe\_engine/runtime][recipe_engine/recipe_modules/runtime]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/presubmit/tests/prepare.py#28)(api, patch_project, patch_repository_url):**
 ### *recipes* / [tryserver:examples/full](/recipes/recipe_modules/tryserver/examples/full.py)
 
 [DEPS](/recipes/recipe_modules/tryserver/examples/full.py#7): [gerrit](#recipe_modules-gerrit), [tryserver](#recipe_modules-tryserver), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [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/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
 
 — **def [RunSteps](/recipes/recipe_modules/tryserver/examples/full.py#22)(api):**
 ### *recipes* / [tryserver:tests/gerrit\_change\_fetch\_ref\_timeout](/recipes/recipe_modules/tryserver/tests/gerrit_change_fetch_ref_timeout.py)
 
 [DEPS](/recipes/recipe_modules/tryserver/tests/gerrit_change_fetch_ref_timeout.py#9): [gerrit](#recipe_modules-gerrit), [tryserver](#recipe_modules-tryserver), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/properties][recipe_engine/recipe_modules/properties]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/tryserver/tests/gerrit_change_fetch_ref_timeout.py#17)(api):**
 ### *recipes* / [tryserver:tests/gerrit\_change\_owner](/recipes/recipe_modules/tryserver/tests/gerrit_change_owner.py)
 
 [DEPS](/recipes/recipe_modules/tryserver/tests/gerrit_change_owner.py#9): [gerrit](#recipe_modules-gerrit), [tryserver](#recipe_modules-tryserver), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/tryserver/tests/gerrit_change_owner.py#16)(api):**
 ### *recipes* / [tryserver:tests/gerrit\_change\_target\_ref](/recipes/recipe_modules/tryserver/tests/gerrit_change_target_ref.py)
 
 [DEPS](/recipes/recipe_modules/tryserver/tests/gerrit_change_target_ref.py#9): [gerrit](#recipe_modules-gerrit), [tryserver](#recipe_modules-tryserver), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [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
 
 — **def [RunSteps](/recipes/recipe_modules/tryserver/tests/gerrit_change_target_ref.py#18)(api):**
 ### *recipes* / [tryserver:tests/get\_files\_affected\_by\_patch](/recipes/recipe_modules/tryserver/tests/get_files_affected_by_patch.py)
 
 [DEPS](/recipes/recipe_modules/tryserver/tests/get_files_affected_by_patch.py#9): [tryserver](#recipe_modules-tryserver), [recipe\_engine/assertions][recipe_engine/recipe_modules/assertions], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/platform][recipe_engine/recipe_modules/platform], [recipe\_engine/properties][recipe_engine/recipe_modules/properties]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/tryserver/tests/get_files_affected_by_patch.py#18)(api):**
 ### *recipes* / [tryserver:tests/require\_is\_tryserver](/recipes/recipe_modules/tryserver/tests/require_is_tryserver.py)
 
 [DEPS](/recipes/recipe_modules/tryserver/tests/require_is_tryserver.py#12): [tryserver](#recipe_modules-tryserver), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/properties][recipe_engine/recipe_modules/properties]
 
-PYTHON_VERSION_COMPATIBILITY: PY2+3
+PYTHON_VERSION_COMPATIBILITY: PY3
 
 — **def [RunSteps](/recipes/recipe_modules/tryserver/tests/require_is_tryserver.py#19)(api):**
 ### *recipes* / [windows\_sdk:examples/full](/recipes/recipe_modules/windows_sdk/examples/full.py)
 
 [DEPS](/recipes/recipe_modules/windows_sdk/examples/full.py#7): [windows\_sdk](#recipe_modules-windows_sdk), [recipe\_engine/json][recipe_engine/recipe_modules/json], [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
 
 — **def [RunSteps](/recipes/recipe_modules/windows_sdk/examples/full.py#16)(api):**