Documentation fix.
diff --git a/Doc/library/ast.rst b/Doc/library/ast.rst
index 4ce21c8..2192d11 100644
--- a/Doc/library/ast.rst
+++ b/Doc/library/ast.rst
@@ -258,5 +258,5 @@
    debugging purposes.  The returned string will show the names and the values
    for fields.  This makes the code impossible to evaluate, so if evaluation is
    wanted *annotate_fields* must be set to False.  Attributes such as line
-   numbers and column offsets are dumped by default.  If this is wanted,
+   numbers and column offsets are not dumped by default.  If this is wanted,
    *include_attributes* can be set to ``True``.