Backport r57105 and r57145 from the py3k branch: UTF-32 codecs.
diff --git a/Lib/encodings/aliases.py b/Lib/encodings/aliases.py
index cefb2ed..c6f5aeb 100644
--- a/Lib/encodings/aliases.py
+++ b/Lib/encodings/aliases.py
@@ -490,6 +490,16 @@
     'unicodelittleunmarked' : 'utf_16_le',
     'utf_16le'           : 'utf_16_le',
 
+    # utf_32 codec
+    'u32'                : 'utf_32',
+    'utf32'              : 'utf_32',
+
+    # utf_32_be codec
+    'utf_32be'           : 'utf_32_be',
+
+    # utf_32_le codec
+    'utf_32le'           : 'utf_32_le',
+
     # utf_7 codec
     'u7'                 : 'utf_7',
     'utf7'               : 'utf_7',