diff --git a/Doc/library/constants.rst b/Doc/library/constants.rst
index 634656a..0d44b7b 100644
--- a/Doc/library/constants.rst
+++ b/Doc/library/constants.rst
@@ -8,7 +8,8 @@
 .. note::
 
    :data:`None`, :data:`False`, :data:`True` and :data:`__debug__` cannot be
-   reassigned, so they can be considered "true" constants.
+   reassigned (assignments to them raise :exc:`SyntaxError`), so they can be
+   considered "true" constants.
 
 .. XXX False, True, None are keywords too
 
diff --git a/Doc/reference/simple_stmts.rst b/Doc/reference/simple_stmts.rst
index e905ff6..e9be1fd 100644
--- a/Doc/reference/simple_stmts.rst
+++ b/Doc/reference/simple_stmts.rst
@@ -290,7 +290,7 @@
 The extended form, ``assert expression1, expression2``, is equivalent to ::
 
    if __debug__:
-      if not expression1: raise AssertionError, expression2
+      if not expression1: raise AssertionError(expression2)
 
 .. index::
    single: __debug__