From 0fa144f0125ba34a5e94d6d59490d14ecbf47d49 Mon Sep 17 00:00:00 2001
From: INADA Naoki <songofacandy@gmail.com>
Date: Fri, 19 Jan 2018 19:54:22 +0900
Subject: [PATCH 1/2] bpo-32596: Lazy import concurrent.futures.process and
 thread

Using module __getattr__ (PEP 562)
---
 Lib/concurrent/futures/__init__.py | 35 ++++++++++++++++++++++++++++--
 1 file changed, 33 insertions(+), 2 deletions(-)

diff --git a/Lib/concurrent/futures/__init__.py b/Lib/concurrent/futures/__init__.py
index ba8de1639050933..72aca818d3ef00e 100644
--- a/Lib/concurrent/futures/__init__.py
+++ b/Lib/concurrent/futures/__init__.py
@@ -15,5 +15,36 @@
                                       Executor,
                                       wait,
                                       as_completed)
-from concurrent.futures.process import ProcessPoolExecutor
-from concurrent.futures.thread import ThreadPoolExecutor
+
+__all__ = (
+    'FIRST_COMPLETED',
+    'FIRST_EXCEPTION',
+    'ALL_COMPLETED',
+    'CancelledError',
+    'TimeoutError',
+    'BrokenExecutor',
+    'Future',
+    'Executor',
+    'wait',
+    'as_completed',
+    'ProcessPoolExecutor',
+    'ThreadPoolExecutor',
+)
+
+
+def __dir__():
+    return __all__ + ('__author__', '__doc__')
+
+
+def __getattr__(name):
+    global ProcessPoolExecutor, ThreadPoolExecutor
+
+    if name == 'ProcessPoolExecutor':
+        from .process import ProcessPoolExecutor
+        return ProcessPoolExecutor
+
+    if name == 'ThreadPoolExecutor':
+        from .thread import ThreadPoolExecutor
+        return ThreadPoolExecutor
+
+    raise AttributeError(f"module {__name__} has no attribute {name}")

From 38d55acdcd537a4239ea01a1b851b50badcab843 Mon Sep 17 00:00:00 2001
From: INADA Naoki <songofacandy@gmail.com>
Date: Fri, 19 Jan 2018 19:57:47 +0900
Subject: [PATCH 2/2] Add NEWS entry

---
 .../next/Library/2018-01-19-19-57-45.bpo-32596.4aVIie.rst     | 4 ++++
 1 file changed, 4 insertions(+)
 create mode 100644 Misc/NEWS.d/next/Library/2018-01-19-19-57-45.bpo-32596.4aVIie.rst

diff --git a/Misc/NEWS.d/next/Library/2018-01-19-19-57-45.bpo-32596.4aVIie.rst b/Misc/NEWS.d/next/Library/2018-01-19-19-57-45.bpo-32596.4aVIie.rst
new file mode 100644
index 000000000000000..a90f7d176539143
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2018-01-19-19-57-45.bpo-32596.4aVIie.rst
@@ -0,0 +1,4 @@
+``concurrent.futures`` imports ``ThreadPoolExecutor`` and
+``ProcessPoolExecutor`` lazily (using :pep:`562`).
+It makes ``import asyncio`` about 15% faster because asyncio
+uses only ``ThreadPoolExecutor`` by default.