Clean fmt documentation

libqtile/widget/base.py

@@ -465,10 +465,9 @@ class _TextBox(_Widget):
         (
             "fmt",
             "{}",
-            "To format the string returned by the widget. For example, if the clock widget \
-             returns '08:46' we can do fmt='time {}' do print 'time 08:46' on the widget. \
-             To format the individual strings like hour and minutes use the format paramater \
-             of the widget (if it has one)",
+            "Format to apply to the string returned by the widget. Main purpose: applying markup. "
+            "For a widget that returns ``foo``, using ``fmt='<i>{}</i>'`` would give you ``'<i>foo</i>'``. "
+            "To control what the widget outputs in the first place, use the ``format`` paramater of the widget (if it has one).",
         ),
         ("max_chars", 0, "Maximum number of characters to display in widget."),
         (