Issue #18874: Implement the PEP 454 (tracemalloc)
diff --git a/Modules/Setup.dist b/Modules/Setup.dist
index ebf8172..01fb85f 100644
--- a/Modules/Setup.dist
+++ b/Modules/Setup.dist
@@ -102,7 +102,7 @@
 # various reasons; therefore they are listed here instead of in the
 # normal order.
 
-# This only contains the minimal set of modules required to run the 
+# This only contains the minimal set of modules required to run the
 # setup.py script in the root of the Python source tree.
 
 posix posixmodule.c		# posix (UNIX) system calls
@@ -115,7 +115,7 @@
 _functools _functoolsmodule.c   # Tools for working with functions and callable objects
 _operator _operator.c	        # operator.add() and similar goodies
 _collections _collectionsmodule.c # Container types
-itertools itertoolsmodule.c    # Functions creating iterators for efficient looping 
+itertools itertoolsmodule.c    # Functions creating iterators for efficient looping
 atexit atexitmodule.c      # Register functions to be run at interpreter-shutdown
 _stat _stat.c			# stat.h interface
 
@@ -132,12 +132,15 @@
 # faulthandler module
 faulthandler faulthandler.c
 
+# debug tool to trace memory blocks allocated by Python
+_tracemalloc _tracemalloc.c hashtable.c
+
 # The rest of the modules listed in this file are all commented out by
 # default.  Usually they can be detected and built as dynamically
 # loaded modules by the new setup.py script added in Python 2.1.  If
-# you're on a platform that doesn't support dynamic loading, want to 
-# compile modules statically into the Python binary, or need to 
-# specify some odd set of compiler switches, you can uncomment the 
+# you're on a platform that doesn't support dynamic loading, want to
+# compile modules statically into the Python binary, or need to
+# specify some odd set of compiler switches, you can uncomment the
 # appropriate lines below.
 
 # ======================================================================
@@ -186,7 +189,7 @@
 # supported...)
 
 #fcntl fcntlmodule.c	# fcntl(2) and ioctl(2)
-#spwd spwdmodule.c		# spwd(3) 
+#spwd spwdmodule.c		# spwd(3)
 #grp grpmodule.c		# grp(3)
 #select selectmodule.c	# select(2); not on ancient System V
 
@@ -302,7 +305,7 @@
 
 #_curses _cursesmodule.c -lcurses -ltermcap
 # Wrapper for the panel library that's part of ncurses and SYSV curses.
-#_curses_panel _curses_panel.c -lpanel -lncurses 
+#_curses_panel _curses_panel.c -lpanel -lncurses
 
 
 # Modules that provide persistent dictionary-like semantics.  You will