#15789: merge with 3.2.

diff --cc Doc/library/subprocess.rst
index 2d5f76192eb409baff6eecc02c69507f177aea38,9c03e06ec661e97ab96a5abd8f658731a73f3de4..042f8f4bca15fc46410685f141ac7f7f94708b36
--- 1/Doc/library/subprocess.rst
--- 2/Doc/library/subprocess.rst
+++ b/Doc/library/subprocess.rst
@@@ -307,17 -245,15 +307,21 @@@ default values. The arguments that are 
        :meth:`Popen.communicate` method.
  
     If *shell* is ``True``, the specified command will be executed through
-    the shell. This can be useful if you are using Python primarily for the
+    the shell.  This can be useful if you are using Python primarily for the
     enhanced control flow it offers over most system shells and still want
-    access to other shell features such as filename wildcards, shell pipes and
-    environment variable expansion.
+    convenient access to other shell features such as shell pipes, filename
+    wildcards, environment variable expansion, and expansion of ``~`` to a
+    user's home directory.  However, note that Python itself offers
+    implementations of many shell-like features (in particular, :mod:`glob`,
+    :mod:`fnmatch`, :func:`os.walk`, :func:`os.path.expandvars`,
+    :func:`os.path.expanduser`, and :mod:`shutil`).
  
 +   .. versionchanged:: 3.3
 +      When *universal_newlines* is ``True``, the class uses the encoding
 +      :func:`locale.getpreferredencoding(False) <locale.getpreferredencoding>`
 +      instead of ``locale.getpreferredencoding()``.  See the
 +      :class:`io.TextIOWrapper` class for more information on this change.
 +
     .. warning::
  
        Executing shell commands that incorporate unsanitized input from an