From c187c899ca476dafb148cdca27564c5ec6cf2241 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Mon, 15 Feb 2010 16:56:33 -0700
Subject: [PATCH] ...

---
 src/calibre/utils/date.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/calibre/utils/date.py b/src/calibre/utils/date.py
index da5a2d3bc2..9a433e3a6d 100644
--- a/src/calibre/utils/date.py
+++ b/src/calibre/utils/date.py
@@ -12,6 +12,10 @@ from dateutil.parser import parse
 from dateutil.tz import tzlocal, tzutc
 
 class SafeLocalTimeZone(tzlocal):
+    '''
+    Assume DST was not in effect for historical dates, if DST
+    data for the local timezone is not present in the operating system.
+    '''
 
     def _isdst(self, dt):
         try: