bpo-9850: Deprecate the macpath module (#1540)

Co-Authored-By: Chi Hsuan Yen <yan12125@gmail.com>.
diff --git a/Doc/library/macpath.rst b/Doc/library/macpath.rst
index b08bbe0..2af51c6 100644
--- a/Doc/library/macpath.rst
+++ b/Doc/library/macpath.rst
@@ -6,6 +6,8 @@
 
 **Source code:** :source:`Lib/macpath.py`
 
+.. deprecated-removed:: 3.7 3.8
+
 --------------
 
 This module is the Mac OS 9 (and earlier) implementation of the :mod:`os.path`
diff --git a/Doc/whatsnew/3.7.rst b/Doc/whatsnew/3.7.rst
index 3a001d7..8e5ac52 100644
--- a/Doc/whatsnew/3.7.rst
+++ b/Doc/whatsnew/3.7.rst
@@ -265,6 +265,8 @@
   now deprecated.  It never correctly worked. (Contributed by Serhiy Storchaka
   in :issue:`28692`.)
 
+- The :mod:`macpath` is now deprecated and will be removed in Python 3.8.
+
 
 Changes in the C API
 --------------------
diff --git a/Lib/macpath.py b/Lib/macpath.py
index a90d105..f85a914 100644
--- a/Lib/macpath.py
+++ b/Lib/macpath.py
@@ -4,6 +4,10 @@
 from stat import *
 import genericpath
 from genericpath import *
+import warnings
+
+warnings.warn('the macpath module is deprecated in 3.7 and will be removed '
+              'in 3.8', DeprecationWarning, stacklevel=2)
 
 __all__ = ["normcase","isabs","join","splitdrive","split","splitext",
            "basename","dirname","commonprefix","getsize","getmtime",
diff --git a/Lib/test/test_macpath.py b/Lib/test/test_macpath.py
index 0698ff5..540bf22 100644
--- a/Lib/test/test_macpath.py
+++ b/Lib/test/test_macpath.py
@@ -1,6 +1,12 @@
-import macpath
 from test import test_genericpath
 import unittest
+import warnings
+
+
+with warnings.catch_warnings():
+    warnings.filterwarnings("ignore", "the macpath module is deprecated",
+                            DeprecationWarning)
+    import macpath
 
 
 class MacPathTestCase(unittest.TestCase):