dbm.dumb was opening files without specifying the encoding. Caused problem on
at least OS X where the default is macroman.

Closes issue #4382.
diff --git a/Misc/NEWS b/Misc/NEWS
index 36cfe41..afc3982 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -22,6 +22,9 @@
 Library
 -------
 
+- Issue #4382: dbm.dumb did not specify the expected file encoding for opened
+  files.
+
 - Issue #4383: When IDLE cannot make the connection to its subprocess, it would
   fail to properly display the error message.