--- a/dot_parser.py.orig	2021-02-15 21:19:47.000000000 +0800
+++ b/dot_parser.py	2022-01-04 16:16:24.522390705 +0800
@@ -439,6 +439,8 @@
 
         noncomma = "".join([c for c in printables if c != ","])
         alphastring_ = OneOrMore(CharsNotIn(noncomma + ' '))
+        # override pyparsing tightened whitespace-skipping logic
+        alphastring_.skipWhitespace = True
 
         def parse_html(s, loc, toks):
             return '<%s>' % ''.join(toks[0])