Issue 6280: Tests and simpler implementation for calendar.timegm
diff --git a/Lib/test/test_calendar.py b/Lib/test/test_calendar.py
index e8b2ca5..b7ce475 100644
--- a/Lib/test/test_calendar.py
+++ b/Lib/test/test_calendar.py
@@ -2,7 +2,7 @@
 import unittest
 
 from test import support
-
+import time
 
 result_2004_text = """
                                   2004
@@ -381,13 +381,21 @@
         # A 31-day december starting on friday (2+7+7+7+7+1 days)
         self.check_weeks(1995, 12, (2, 7, 7, 7, 7, 1))
 
+class TimegmTestCase(unittest.TestCase):
+    TIMESTAMPS = [0, 10, 100, 1000, 10000, 100000, 1000000,
+                  1234567890, 1262304000, 1275785153,]
+    def test_timegm(self):
+        for secs in self.TIMESTAMPS:
+            tuple = time.gmtime(secs)
+            self.assertEqual(secs, calendar.timegm(tuple))
 
 def test_main():
     support.run_unittest(
         OutputTestCase,
         CalendarTestCase,
         MondayTestCase,
-        SundayTestCase
+        SundayTestCase,
+        TimegmTestCase,
     )