diff --git a/doc/sphinxext/announce.py b/doc/sphinxext/announce.py
index e4859157f73de..0084036f1e75c 100755
--- a/doc/sphinxext/announce.py
+++ b/doc/sphinxext/announce.py
@@ -122,14 +122,15 @@ def build_string(revision_range, heading="Contributors"):
     components["uline"] = "=" * len(components["heading"])
     components["authors"] = "* " + "\n* ".join(components["authors"])
 
+    # Don't change this to an fstring. It breaks the formatting.
     tpl = textwrap.dedent(
-        f"""\
-    {components['heading']}
-    {components['uline']}
+        """\
+    {heading}
+    {uline}
 
-    {components['author_message']}
-    {components['authors']}"""
-    )
+    {author_message}
+    {authors}"""
+    ).format(**components)
     return tpl