Issue #26778: Fixed "a/an/and" typos in code comment and documentation.
diff --git a/Tools/msi/msi.py b/Tools/msi/msi.py
index a56e40a..3ef4a65 100644
--- a/Tools/msi/msi.py
+++ b/Tools/msi/msi.py
@@ -259,7 +259,7 @@
     # either both per-machine or per-user.
     migrate_features = 1
     # See "Upgrade Table". We remove releases with the same major and
-    # minor version. For an snapshot, we remove all earlier snapshots. For
+    # minor version. For a snapshot, we remove all earlier snapshots. For
     # a release, we remove all snapshots, and all earlier releases.
     if snapshot:
         add_data(db, "Upgrade",