Fix empty strings to empty bytes objects.
diff --git a/Doc/library/xml.etree.elementtree.rst b/Doc/library/xml.etree.elementtree.rst
index cf65219..3f2dcbb 100644
--- a/Doc/library/xml.etree.elementtree.rst
+++ b/Doc/library/xml.etree.elementtree.rst
@@ -457,7 +457,7 @@
is either ``"xml"``, ``"html"`` or ``"text"`` (default is ``"xml"``).
Returns a list of (optionally) encoded strings containing the XML data.
It does not guarantee any specific sequence, except that
- ``"".join(tostringlist(element)) == tostring(element)``.
+ ``b"".join(tostringlist(element)) == tostring(element)``.
.. versionadded:: 3.2