doc/runrst

--- a/doc/runrst	Thu Nov 14 21:58:36 2019 -0800
+++ b/doc/runrst	Sat Nov 16 11:59:22 2019 -0800
@@ -27,8 +27,7 @@
                      "http://docutils.sourceforge.net/\n")
     sys.exit(-1)
 
-def role_hg(name, rawtext, text, lineno, inliner,
-            options={}, content=[]):
+def role_hg(name, rawtext, text, lineno, inliner, options=None, content=None):
     text = "hg " + utils.unescape(text)
     linktext = nodes.literal(rawtext, text)
     parts = text.split()