bpo-45557: Fix underscore_numbers in pprint.pprint(). (GH-29129)

(cherry picked from commit 087f089)

Co-authored-by: Eric V. Smith <[email protected]>

Author: miss-islington

Lib/pprint.py

@@ -50,7 +50,8 @@ def pprint(object, stream=None, indent=1, width=80, depth=None, *,
     """Pretty-print a Python object to a stream [default is sys.stdout]."""
     printer = PrettyPrinter(
         stream=stream, indent=indent, width=width, depth=depth,
-        compact=compact, sort_dicts=sort_dicts, underscore_numbers=False)
+        compact=compact, sort_dicts=sort_dicts,
+        underscore_numbers=underscore_numbers)
     printer.pprint(object)
 
 def pformat(object, indent=1, width=80, depth=None, *,

Misc/NEWS.d/next/Library/2021-10-21-16-18-51.bpo-45557.4MQt4r.rst

@@ -0,0 +1,2 @@
+pprint.pprint() now handles underscore_numbers correctly. Previously it was
+always setting it to False.