From 1642978cc9cacaa8089bfe29673daf18f1fe2477 Mon Sep 17 00:00:00 2001
From: Takeshi KOMIYA <i.tkomiya@gmail.com>
Date: Sat, 14 Dec 2019 23:18:27 +0900
Subject: [PATCH] Fix mypy violation

---
 sphinx/writers/html.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sphinx/writers/html.py b/sphinx/writers/html.py
index 4eade8453..11a9bbbc4 100644
--- a/sphinx/writers/html.py
+++ b/sphinx/writers/html.py
@@ -289,6 +289,8 @@ class HTMLTranslator(SphinxTranslator, BaseTranslator):
             if self.builder.secnumbers.get(anchorname):
                 return self.builder.secnumbers[anchorname]
 
+        return None
+
     def add_secnumber(self, node: Element) -> None:
         secnumber = self.get_secnumber(node)
         if secnumber: