Bump main branch version number to 6.4.dev1

diff --git a/tornado/__init__.py b/tornado/__init__.py
index afbd715053dbe9c24c99e765ec300de244a1bcc2..3df733ad980262a5d1cea8892e9bbe8027bab74e 100644 (file)
--- a/tornado/__init__.py
+++ b/tornado/__init__.py
@@ -22,8 +22,8 @@
 # is zero for an official release, positive for a development branch,
 # or negative for a release candidate or beta (after the base version
 # number has been incremented)
-version = "6.3.1"
-version_info = (6, 3, 1, 0)
+version = "6.4.dev1"
+version_info = (6, 4, 0, -100)
 
 import importlib
 import typing