Issue #13959: Deprecate imp.get_suffixes() for new attributes on

importlib.machinery that provide the suffix details for import.
The attributes were not put on imp so as to compartmentalize
everything importlib needs for setting up imports in
importlib.machinery.

This also led to an indirect deprecation of inspect.getmoduleinfo() as
it directly returned imp.get_suffix's returned tuple which no longer
makes sense.

Lib/importlib/test/extension/util.py

@@ -1,4 +1,5 @@
 import imp
+from importlib import machinery
 import os
 import sys
 
@@ -6,10 +7,9 @@ PATH = None
 EXT = None
 FILENAME = None
 NAME = '_testcapi'
-_file_exts = [x[0] for x in imp.get_suffixes() if x[2] == imp.C_EXTENSION]
 try:
     for PATH in sys.path:
-        for EXT in _file_exts:
+        for EXT in machinery.EXTENSION_SUFFIXES:
             FILENAME = NAME + EXT
             FILEPATH = os.path.join(PATH, FILENAME)
             if os.path.exists(os.path.join(PATH, FILENAME)):
@@ -18,4 +18,3 @@ try:
         PATH = EXT = FILENAME = FILEPATH = None
 except StopIteration:
     pass
-del _file_exts