bpo-43651: Fix EncodingWarning in `pydoc`. (GH-25644)

diff --git a/Lib/pydoc.py b/Lib/pydoc.py
index 753ea97ba0c2a77b917b2f7ed387f42c8c8fb40d..8eecd66a2c2fbf3c2e910868dc0cfac265c383e0 100755 (executable)
--- a/Lib/pydoc.py
+++ b/Lib/pydoc.py
@@ -1594,9 +1594,10 @@ def plain(text):
 def pipepager(text, cmd):
     """Page through text by feeding it to another program."""
     import subprocess
-    proc = subprocess.Popen(cmd, shell=True, stdin=subprocess.PIPE)
+    proc = subprocess.Popen(cmd, shell=True, stdin=subprocess.PIPE,
+                            errors='backslashreplace')
     try:
-        with io.TextIOWrapper(proc.stdin, errors='backslashreplace') as pipe:
+        with proc.stdin as pipe:
             try:
                 pipe.write(text)
             except KeyboardInterrupt: