Issue #19795: Mark up None as literal text.
diff --git a/Doc/library/turtle.rst b/Doc/library/turtle.rst
index 01da6a0..ca4f37e 100644
--- a/Doc/library/turtle.rst
+++ b/Doc/library/turtle.rst
@@ -529,7 +529,7 @@
:param n: an integer (or ``None``)
- Delete all or first/last *n* of turtle's stamps. If *n* is None, delete
+ Delete all or first/last *n* of turtle's stamps. If *n* is ``None``, delete
all stamps, if *n* > 0 delete first *n* stamps, else if *n* < 0 delete
last *n* stamps.
@@ -1857,10 +1857,10 @@
:param height: if an integer, the height in pixels, if a float, a fraction of
the screen; default is 75% of screen
:param startx: if positive, starting position in pixels from the left
- edge of the screen, if negative from the right edge, if None,
+ edge of the screen, if negative from the right edge, if ``None``,
center window horizontally
:param starty: if positive, starting position in pixels from the top
- edge of the screen, if negative from the bottom edge, if None,
+ edge of the screen, if negative from the bottom edge, if ``None``,
center window vertically
.. doctest::