diff --git a/pymongo/_version.py b/pymongo/_version.py
index 770cc2b65..9022b2c15 100644
--- a/pymongo/_version.py
+++ b/pymongo/_version.py
@@ -15,7 +15,7 @@
 """Current version of PyMongo."""
 from typing import Tuple, Union
 
-version_tuple: Tuple[Union[int, str], ...] = (4, 6, 0, '.dev0')
+version_tuple: Tuple[Union[int, str], ...] = (4, 6, 0, ".dev0")
 
 
 def get_version_string() -> str: