diff --git a/Lib/datetime.py b/Lib/datetime.py
--- a/Lib/datetime.py
+++ b/Lib/datetime.py
@@ -7,6 +7,9 @@
 import time as _time
 import math as _math
 
+# Sentinel value to disallow None
+_SENTINEL = object()
+
 def _cmp(x, y):
     return 0 if x == y else 1 if x > y else -1
 
@@ -14,6 +17,8 @@
 MAXYEAR = 9999
 _MAXORDINAL = 3652059  # date.max.toordinal()
 
+_MAX_DELTA_DAYS = 999999999
+
 # Utility functions, adapted from Python's Demo/classes/Dates.py, which
 # also assumes the current Gregorian calendar indefinitely extended in
 # both directions.  Difference:  Dates.py calls January 1 of year 0 day
@@ -79,6 +84,15 @@
 # pasting together 25 4-year cycles.
 assert _DI100Y == 25 * _DI4Y - 1
 
+_US_PER_US = 1
+_US_PER_MS = 1000
+_US_PER_SECOND = 1000000
+_US_PER_MINUTE = 60000000
+_SECONDS_PER_DAY = 24 * 3600
+_US_PER_HOUR = 3600000000
+_US_PER_DAY = 86400000000
+_US_PER_WEEK = 604800000000
+
 def _ord2ymd(n):
     "ordinal -> (year, month, day), considering 01-Jan-0001 as day 1."
 
@@ -146,6 +160,24 @@
                      "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
 _DAYNAMES = [None, "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"]
 
+def _accum(tag, sofar, num, factor, leftover):
+    if isinstance(num, int):
+        prod = num * factor
+        result = sofar + prod
+        return result, leftover
+    if isinstance(num, float):
+        fracpart, intpart = _math.modf(num)
+        prod = int(intpart) * factor
+        result = sofar + prod
+        if fracpart == 0.0:
+            return result, leftover
+        assert isinstance(factor, int)
+        fracpart, intpart = _math.modf(factor * fracpart)
+        result += int(intpart)
+        return result, leftover + fracpart
+    raise TypeError("unsupported type for timedelta %s component: %s" %
+                    (tag, type(num)))
+
 
 def _build_struct_time(y, m, d, hh, mm, ss, dstflag):
     wday = (_ymd2ord(y, m, d) + 6) % 7
@@ -543,7 +575,7 @@
     __rmul__ = __mul__
 
     def _to_microseconds(self):
-        return ((self._days * (24*3600) + self._seconds) * 1000000 +
+        return ((self._days * _SECONDS_PER_DAY + self._seconds) * _US_PER_SECOND +
                 self._microseconds)
 
     def __floordiv__(self, other):
@@ -634,9 +666,8 @@
     def __reduce__(self):
         return (self.__class__, self._getstate())
 
-timedelta.min = timedelta(-999999999)
-timedelta.max = timedelta(days=999999999, hours=23, minutes=59, seconds=59,
-                          microseconds=999999)
+timedelta.min = timedelta(-_MAX_DELTA_DAYS)
+timedelta.max = timedelta(_MAX_DELTA_DAYS, 24*3600-1, 1000000-1)
 timedelta.resolution = timedelta(microseconds=1)
 
 class date:
@@ -1816,11 +1847,10 @@
     __slots__ = '_offset', '_name'
 
     # Sentinel value to disallow None
-    _Omitted = object()
-    def __new__(cls, offset, name=_Omitted):
+    def __new__(cls, offset, name=_SENTINEL):
         if not isinstance(offset, timedelta):
             raise TypeError("offset must be a timedelta")
-        if name is cls._Omitted:
+        if name is _SENTINEL:
             if not offset:
                 return cls.utc
             name = None
diff --git a/Lib/test/datetimetester.py b/Lib/test/datetimetester.py
--- a/Lib/test/datetimetester.py
+++ b/Lib/test/datetimetester.py
@@ -64,7 +64,7 @@
         self.assertEqual(names - allowed, set([]))
 
     def test_divide_and_round(self):
-        if '_Fast' in str(self):
+        if '_Fast' in type(self).__name__:
             return
         dar = datetime_module._divide_and_round