Issue #17177: The imp module is pending deprecation.

To make sure there is no issue with code that is both Python 2 and 3
compatible, there are no plans to remove the module any sooner than
Python 4 (unless the community moves to Python 3 solidly before then).
diff --git a/Lib/modulefinder.py b/Lib/modulefinder.py
index 4996d7a..e3ad7d6 100644
--- a/Lib/modulefinder.py
+++ b/Lib/modulefinder.py
@@ -1,13 +1,16 @@
 """Find modules used by a script, using introspection."""
 
 import dis
-import imp
 import importlib.machinery
 import marshal
 import os
 import sys
 import types
 import struct
+import warnings
+with warnings.catch_warnings():
+    warnings.simplefilter('ignore', PendingDeprecationWarning)
+    import imp
 
 # XXX Clean up once str8's cstor matches bytes.
 LOAD_CONST = bytes([dis.opname.index('LOAD_CONST')])