Add cross-references to the glossary entry for file objects.
diff --git a/Doc/library/formatter.rst b/Doc/library/formatter.rst
index 0a459a6..88be11c 100644
--- a/Doc/library/formatter.rst
+++ b/Doc/library/formatter.rst
@@ -339,8 +339,8 @@
.. class:: DumbWriter(file=None, maxcol=72)
- Simple writer class which writes output on the file object passed in as *file*
- or, if *file* is omitted, on standard output. The output is simply word-wrapped
- to the number of columns specified by *maxcol*. This class is suitable for
- reflowing a sequence of paragraphs.
+ Simple writer class which writes output on the :term:`file object` passed
+ in as *file* or, if *file* is omitted, on standard output. The output is
+ simply word-wrapped to the number of columns specified by *maxcol*. This
+ class is suitable for reflowing a sequence of paragraphs.