diff --git a/Lib/decimal.py b/Lib/decimal.py
index 55faf99..873f7c0 100644
--- a/Lib/decimal.py
+++ b/Lib/decimal.py
@@ -802,7 +802,7 @@
     #   != comparisons involving a NaN always return True
     #   <, >, <= and >= comparisons involving a (quiet or signaling)
     #      NaN signal InvalidOperation, and return False if the
-    #      InvalidOperation is trapped.
+    #      InvalidOperation is not trapped.
     #
     # This behavior is designed to conform as closely as possible to
     # that specified by IEEE 754.
diff --git a/Lib/rational.py b/Lib/fractions.py
similarity index 83%
rename from Lib/rational.py
rename to Lib/fractions.py
index 6002964..25b9f02 100755
--- a/Lib/rational.py
+++ b/Lib/fractions.py
@@ -1,16 +1,15 @@
 # Originally contributed by Sjoerd Mullender.
 # Significantly modified by Jeffrey Yasskin <jyasskin at gmail.com>.
 
-"""Rational, infinite-precision, real numbers."""
+"""Fraction, infinite-precision, real numbers."""
 
 import math
 import numbers
 import operator
 import re
 
-__all__ = ["Rational"]
+__all__ = ["Fraction"]
 
-RationalAbc = numbers.Rational
 
 
 def gcd(a, b):
@@ -38,15 +37,15 @@
 """, re.VERBOSE)
 
 
-class Rational(RationalAbc):
+class Fraction(numbers.Rational):
     """This class implements rational numbers.
 
-    Rational(8, 6) will produce a rational number equivalent to
+    Fraction(8, 6) will produce a rational number equivalent to
     4/3. Both arguments must be Integral. The numerator defaults to 0
-    and the denominator defaults to 1 so that Rational(3) == 3 and
-    Rational() == 0.
+    and the denominator defaults to 1 so that Fraction(3) == 3 and
+    Fraction() == 0.
 
-    Rationals can also be constructed from strings of the form
+    Fraction can also be constructed from strings of the form
     '[-+]?[0-9]+((/|.)[0-9]+)?', optionally surrounded by spaces.
 
     """
@@ -61,7 +60,7 @@
         numerator/denominator pair.
 
         """
-        self = super(Rational, cls).__new__(cls)
+        self = super(Fraction, cls).__new__(cls)
 
         if denominator == 1:
             if isinstance(numerator, str):
@@ -69,7 +68,7 @@
                 input = numerator
                 m = _RATIONAL_FORMAT.match(input)
                 if m is None:
-                    raise ValueError('Invalid literal for Rational: ' + input)
+                    raise ValueError('Invalid literal for Fraction: ' + input)
                 numerator = m.group('num')
                 decimal = m.group('decimal')
                 if decimal:
@@ -86,7 +85,7 @@
                     numerator = -numerator
 
             elif (not isinstance(numerator, numbers.Integral) and
-                  isinstance(numerator, RationalAbc)):
+                  isinstance(numerator, numbers.Rational)):
                 # Handle copies from other rationals.
                 other_rational = numerator
                 numerator = other_rational.numerator
@@ -94,11 +93,11 @@
 
         if (not isinstance(numerator, numbers.Integral) or
             not isinstance(denominator, numbers.Integral)):
-            raise TypeError("Rational(%(numerator)s, %(denominator)s):"
+            raise TypeError("Fraction(%(numerator)s, %(denominator)s):"
                             " Both arguments must be integral." % locals())
 
         if denominator == 0:
-            raise ZeroDivisionError('Rational(%s, 0)' % numerator)
+            raise ZeroDivisionError('Fraction(%s, 0)' % numerator)
 
         g = gcd(numerator, denominator)
         self._numerator = int(numerator // g)
@@ -109,7 +108,7 @@
     def from_float(cls, f):
         """Converts a finite float to a rational number, exactly.
 
-        Beware that Rational.from_float(0.3) != Rational(3, 10).
+        Beware that Fraction.from_float(0.3) != Fraction(3, 10).
 
         """
         if not isinstance(f, float):
@@ -141,7 +140,7 @@
 
     @classmethod
     def from_continued_fraction(cls, seq):
-        'Build a Rational from a continued fraction expessed as a sequence'
+        'Build a Fraction from a continued fraction expessed as a sequence'
         n, d = 1, 0
         for e in reversed(seq):
             n, d = d, n
@@ -168,7 +167,7 @@
         if self.denominator <= max_denominator:
             return self
         cf = self.as_continued_fraction()
-        result = Rational(0)
+        result = Fraction(0)
         for i in range(1, len(cf)):
             new = self.from_continued_fraction(cf[:i])
             if new.denominator > max_denominator:
@@ -186,7 +185,7 @@
 
     def __repr__(self):
         """repr(self)"""
-        return ('Rational(%r,%r)' % (self.numerator, self.denominator))
+        return ('Fraction(%r,%r)' % (self.numerator, self.denominator))
 
     def __str__(self):
         """str(self)"""
@@ -206,13 +205,13 @@
         that mixed-mode operations either call an implementation whose
         author knew about the types of both arguments, or convert both
         to the nearest built in type and do the operation there. In
-        Rational, that means that we define __add__ and __radd__ as:
+        Fraction, that means that we define __add__ and __radd__ as:
 
             def __add__(self, other):
                 # Both types have numerators/denominator attributes,
                 # so do the operation directly
-                if isinstance(other, (int, Rational)):
-                    return Rational(self.numerator * other.denominator +
+                if isinstance(other, (int, Fraction)):
+                    return Fraction(self.numerator * other.denominator +
                                     other.numerator * self.denominator,
                                     self.denominator * other.denominator)
                 # float and complex don't have those operations, but we
@@ -227,8 +226,8 @@
             def __radd__(self, other):
                 # radd handles more types than add because there's
                 # nothing left to fall back to.
-                if isinstance(other, RationalAbc):
-                    return Rational(self.numerator * other.denominator +
+                if isinstance(other, numbers.Rational):
+                    return Fraction(self.numerator * other.denominator +
                                     other.numerator * self.denominator,
                                     self.denominator * other.denominator)
                 elif isinstance(other, Real):
@@ -239,32 +238,32 @@
 
 
         There are 5 different cases for a mixed-type addition on
-        Rational. I'll refer to all of the above code that doesn't
-        refer to Rational, float, or complex as "boilerplate". 'r'
-        will be an instance of Rational, which is a subtype of
-        RationalAbc (r : Rational <: RationalAbc), and b : B <:
+        Fraction. I'll refer to all of the above code that doesn't
+        refer to Fraction, float, or complex as "boilerplate". 'r'
+        will be an instance of Fraction, which is a subtype of
+        Rational (r : Fraction <: Rational), and b : B <:
         Complex. The first three involve 'r + b':
 
-            1. If B <: Rational, int, float, or complex, we handle
+            1. If B <: Fraction, int, float, or complex, we handle
                that specially, and all is well.
-            2. If Rational falls back to the boilerplate code, and it
+            2. If Fraction falls back to the boilerplate code, and it
                were to return a value from __add__, we'd miss the
                possibility that B defines a more intelligent __radd__,
                so the boilerplate should return NotImplemented from
-               __add__. In particular, we don't handle RationalAbc
+               __add__. In particular, we don't handle Rational
                here, even though we could get an exact answer, in case
                the other type wants to do something special.
-            3. If B <: Rational, Python tries B.__radd__ before
-               Rational.__add__. This is ok, because it was
-               implemented with knowledge of Rational, so it can
+            3. If B <: Fraction, Python tries B.__radd__ before
+               Fraction.__add__. This is ok, because it was
+               implemented with knowledge of Fraction, so it can
                handle those instances before delegating to Real or
                Complex.
 
         The next two situations describe 'b + r'. We assume that b
-        didn't know about Rational in its implementation, and that it
+        didn't know about Fraction in its implementation, and that it
         uses similar boilerplate code:
 
-            4. If B <: RationalAbc, then __radd_ converts both to the
+            4. If B <: Rational, then __radd_ converts both to the
                builtin rational type (hey look, that's us) and
                proceeds.
             5. Otherwise, __radd__ tries to find the nearest common
@@ -276,7 +275,7 @@
 
         """
         def forward(a, b):
-            if isinstance(b, (int, Rational)):
+            if isinstance(b, (int, Fraction)):
                 return monomorphic_operator(a, b)
             elif isinstance(b, float):
                 return fallback_operator(float(a), b)
@@ -288,7 +287,7 @@
         forward.__doc__ = monomorphic_operator.__doc__
 
         def reverse(b, a):
-            if isinstance(a, RationalAbc):
+            if isinstance(a, numbers.Rational):
                 # Includes ints.
                 return monomorphic_operator(a, b)
             elif isinstance(a, numbers.Real):
@@ -304,7 +303,7 @@
 
     def _add(a, b):
         """a + b"""
-        return Rational(a.numerator * b.denominator +
+        return Fraction(a.numerator * b.denominator +
                         b.numerator * a.denominator,
                         a.denominator * b.denominator)
 
@@ -312,7 +311,7 @@
 
     def _sub(a, b):
         """a - b"""
-        return Rational(a.numerator * b.denominator -
+        return Fraction(a.numerator * b.denominator -
                         b.numerator * a.denominator,
                         a.denominator * b.denominator)
 
@@ -320,13 +319,13 @@
 
     def _mul(a, b):
         """a * b"""
-        return Rational(a.numerator * b.numerator, a.denominator * b.denominator)
+        return Fraction(a.numerator * b.numerator, a.denominator * b.denominator)
 
     __mul__, __rmul__ = _operator_fallbacks(_mul, operator.mul)
 
     def _div(a, b):
         """a / b"""
-        return Rational(a.numerator * b.denominator,
+        return Fraction(a.numerator * b.denominator,
                         a.denominator * b.numerator)
 
     __truediv__, __rtruediv__ = _operator_fallbacks(_div, operator.truediv)
@@ -357,14 +356,14 @@
         result will be rational.
 
         """
-        if isinstance(b, RationalAbc):
+        if isinstance(b, numbers.Rational):
             if b.denominator == 1:
                 power = b.numerator
                 if power >= 0:
-                    return Rational(a.numerator ** power,
+                    return Fraction(a.numerator ** power,
                                     a.denominator ** power)
                 else:
-                    return Rational(a.denominator ** -power,
+                    return Fraction(a.denominator ** -power,
                                     a.numerator ** -power)
             else:
                 # A fractional power will generally produce an
@@ -379,8 +378,8 @@
             # If a is an int, keep it that way if possible.
             return a ** b.numerator
 
-        if isinstance(a, RationalAbc):
-            return Rational(a.numerator, a.denominator) ** b
+        if isinstance(a, numbers.Rational):
+            return Fraction(a.numerator, a.denominator) ** b
 
         if b.denominator == 1:
             return a ** b.numerator
@@ -388,16 +387,16 @@
         return a ** float(b)
 
     def __pos__(a):
-        """+a: Coerces a subclass instance to Rational"""
-        return Rational(a.numerator, a.denominator)
+        """+a: Coerces a subclass instance to Fraction"""
+        return Fraction(a.numerator, a.denominator)
 
     def __neg__(a):
         """-a"""
-        return Rational(-a.numerator, a.denominator)
+        return Fraction(-a.numerator, a.denominator)
 
     def __abs__(a):
         """abs(a)"""
-        return Rational(abs(a.numerator), a.denominator)
+        return Fraction(abs(a.numerator), a.denominator)
 
     def __trunc__(a):
         """trunc(a)"""
@@ -433,12 +432,12 @@
                 return floor + 1
         shift = 10**abs(ndigits)
         # See _operator_fallbacks.forward to check that the results of
-        # these operations will always be Rational and therefore have
+        # these operations will always be Fraction and therefore have
         # round().
         if ndigits > 0:
-            return Rational(round(self * shift), shift)
+            return Fraction(round(self * shift), shift)
         else:
-            return Rational(round(self / shift) * shift)
+            return Fraction(round(self / shift) * shift)
 
     def __hash__(self):
         """hash(self)
@@ -461,7 +460,7 @@
 
     def __eq__(a, b):
         """a == b"""
-        if isinstance(b, RationalAbc):
+        if isinstance(b, numbers.Rational):
             return (a.numerator == b.numerator and
                     a.denominator == b.denominator)
         if isinstance(b, numbers.Complex) and b.imag == 0:
@@ -488,7 +487,7 @@
         if isinstance(b, float):
             b = a.from_float(b)
         try:
-            # XXX: If b <: Real but not <: RationalAbc, this is likely
+            # XXX: If b <: Real but not <: Rational, this is likely
             # to fall back to a float. If the actual values differ by
             # less than MIN_FLOAT, this could falsely call them equal,
             # which would make <= inconsistent with ==. Better ways of
@@ -496,7 +495,7 @@
             diff = a - b
         except TypeError:
             return NotImplemented
-        if isinstance(diff, RationalAbc):
+        if isinstance(diff, numbers.Rational):
             return op(diff.numerator, 0)
         return op(diff, 0)
 
@@ -526,11 +525,11 @@
         return (self.__class__, (str(self),))
 
     def __copy__(self):
-        if type(self) == Rational:
+        if type(self) == Fraction:
             return self     # I'm immutable; therefore I am my own clone
         return self.__class__(self.numerator, self.denominator)
 
     def __deepcopy__(self, memo):
-        if type(self) == Rational:
+        if type(self) == Fraction:
             return self     # My components are also immutable
         return self.__class__(self.numerator, self.denominator)
diff --git a/Lib/pickletools.py b/Lib/pickletools.py
index 0665cd0..1b6967a 100644
--- a/Lib/pickletools.py
+++ b/Lib/pickletools.py
@@ -14,9 +14,7 @@
 import pickle
 import re
 
-__all__ = ['dis',
-           'genops',
-          ]
+__all__ = ['dis', 'genops', 'optimize']
 
 bytes_types = pickle.bytes_types
 
@@ -1836,6 +1834,33 @@
             break
 
 ##############################################################################
+# A pickle optimizer.
+
+def optimize(p):
+    'Optimize a pickle string by removing unused PUT opcodes'
+    gets = set()            # set of args used by a GET opcode
+    puts = []               # (arg, startpos, stoppos) for the PUT opcodes
+    prevpos = None          # set to pos if previous opcode was a PUT
+    for opcode, arg, pos in genops(p):
+        if prevpos is not None:
+            puts.append((prevarg, prevpos, pos))
+            prevpos = None
+        if 'PUT' in opcode.name:
+            prevarg, prevpos = arg, pos
+        elif 'GET' in opcode.name:
+            gets.add(arg)
+
+    # Copy the pickle string except for PUTS without a corresponding GET
+    s = []
+    i = 0
+    for arg, start, stop in puts:
+        j = stop if (arg in gets) else start
+        s.append(p[i:j])
+        i = stop
+    s.append(p[i:])
+    return ''.join(s)
+
+##############################################################################
 # A symbolic pickle disassembler.
 
 def dis(pickle, out=None, memo=None, indentlevel=4):
diff --git a/Lib/test/test_builtin.py b/Lib/test/test_builtin.py
index b17133a..f781db3 100644
--- a/Lib/test/test_builtin.py
+++ b/Lib/test/test_builtin.py
@@ -5,7 +5,7 @@
                               run_with_locale
 from operator import neg
 
-import sys, warnings, random, collections, io, rational
+import sys, warnings, random, collections, io, rational, fractions
 warnings.filterwarnings("ignore", "hex../oct.. of negative int",
                         FutureWarning, __name__)
 warnings.filterwarnings("ignore", "integer argument expected",
@@ -607,7 +607,7 @@
             n, d = f.as_integer_ratio()
             self.assertEqual(float(n).__truediv__(d), f)
 
-        R = rational.Rational
+        R = fractions.Fraction
         self.assertEqual(R(0, 1),
                          R(*float(0.0).as_integer_ratio()))
         self.assertEqual(R(5, 2),
diff --git a/Lib/test/test_rational.py b/Lib/test/test_fractions.py
similarity index 90%
rename from Lib/test/test_rational.py
rename to Lib/test/test_fractions.py
index 92d8a14..00fd549 100644
--- a/Lib/test/test_rational.py
+++ b/Lib/test/test_fractions.py
@@ -1,15 +1,15 @@
-"""Tests for Lib/rational.py."""
+"""Tests for Lib/fractions.py."""
 
 from decimal import Decimal
 from test.test_support import run_unittest, verbose
 import math
 import operator
-import rational
+import fractions
 import unittest
 from copy import copy, deepcopy
 from pickle import dumps, loads
-R = rational.Rational
-gcd = rational.gcd
+R = fractions.Fraction
+gcd = fractions.gcd
 
 
 class GcdTest(unittest.TestCase):
@@ -31,7 +31,7 @@
     return (r.numerator, r.denominator)
 
 
-class RationalTest(unittest.TestCase):
+class FractionTest(unittest.TestCase):
 
     def assertTypedEquals(self, expected, actual):
         """Asserts that both the types and values are the same."""
@@ -60,7 +60,7 @@
         self.assertEquals((7, 15), _components(R(7, 15)))
         self.assertEquals((10**23, 1), _components(R(10**23)))
 
-        self.assertRaisesMessage(ZeroDivisionError, "Rational(12, 0)",
+        self.assertRaisesMessage(ZeroDivisionError, "Fraction(12, 0)",
                                  R, 12, 0)
         self.assertRaises(TypeError, R, 1.5)
         self.assertRaises(TypeError, R, 1.5 + 3j)
@@ -81,41 +81,41 @@
         self.assertEquals((3, 5), _components(R(" .6 ")))
 
         self.assertRaisesMessage(
-            ZeroDivisionError, "Rational(3, 0)",
+            ZeroDivisionError, "Fraction(3, 0)",
             R, "3/0")
         self.assertRaisesMessage(
-            ValueError, "Invalid literal for Rational: 3/",
+            ValueError, "Invalid literal for Fraction: 3/",
             R, "3/")
         self.assertRaisesMessage(
-            ValueError, "Invalid literal for Rational: 3 /2",
+            ValueError, "Invalid literal for Fraction: 3 /2",
             R, "3 /2")
         self.assertRaisesMessage(
             # Denominators don't need a sign.
-            ValueError, "Invalid literal for Rational: 3/+2",
+            ValueError, "Invalid literal for Fraction: 3/+2",
             R, "3/+2")
         self.assertRaisesMessage(
             # Imitate float's parsing.
-            ValueError, "Invalid literal for Rational: + 3/2",
+            ValueError, "Invalid literal for Fraction: + 3/2",
             R, "+ 3/2")
         self.assertRaisesMessage(
             # Avoid treating '.' as a regex special character.
-            ValueError, "Invalid literal for Rational: 3a2",
+            ValueError, "Invalid literal for Fraction: 3a2",
             R, "3a2")
         self.assertRaisesMessage(
             # Only parse ordinary decimals, not scientific form.
-            ValueError, "Invalid literal for Rational: 3.2e4",
+            ValueError, "Invalid literal for Fraction: 3.2e4",
             R, "3.2e4")
         self.assertRaisesMessage(
             # Don't accept combinations of decimals and rationals.
-            ValueError, "Invalid literal for Rational: 3/7.2",
+            ValueError, "Invalid literal for Fraction: 3/7.2",
             R, "3/7.2")
         self.assertRaisesMessage(
             # Don't accept combinations of decimals and rationals.
-            ValueError, "Invalid literal for Rational: 3.2/7",
+            ValueError, "Invalid literal for Fraction: 3.2/7",
             R, "3.2/7")
         self.assertRaisesMessage(
             # Allow 3. and .3, but not .
-            ValueError, "Invalid literal for Rational: .",
+            ValueError, "Invalid literal for Fraction: .",
             R, ".")
 
     def testImmutable(self):
@@ -136,7 +136,7 @@
 
     def testFromFloat(self):
         self.assertRaisesMessage(
-            TypeError, "Rational.from_float() only takes floats, not 3 (int)",
+            TypeError, "Fraction.from_float() only takes floats, not 3 (int)",
             R.from_float, 3)
 
         self.assertEquals((0, 1), _components(R.from_float(-0.0)))
@@ -152,19 +152,19 @@
         inf = 1e1000
         nan = inf - inf
         self.assertRaisesMessage(
-            TypeError, "Cannot convert inf to Rational.",
+            TypeError, "Cannot convert inf to Fraction.",
             R.from_float, inf)
         self.assertRaisesMessage(
-            TypeError, "Cannot convert -inf to Rational.",
+            TypeError, "Cannot convert -inf to Fraction.",
             R.from_float, -inf)
         self.assertRaisesMessage(
-            TypeError, "Cannot convert nan to Rational.",
+            TypeError, "Cannot convert nan to Fraction.",
             R.from_float, nan)
 
     def testFromDecimal(self):
         self.assertRaisesMessage(
             TypeError,
-            "Rational.from_decimal() only takes Decimals, not 3 (int)",
+            "Fraction.from_decimal() only takes Decimals, not 3 (int)",
             R.from_decimal, 3)
         self.assertEquals(R(0), R.from_decimal(Decimal("-0")))
         self.assertEquals(R(5, 10), R.from_decimal(Decimal("0.5")))
@@ -174,16 +174,16 @@
                           R.from_decimal(Decimal("0." + "9" * 30)))
 
         self.assertRaisesMessage(
-            TypeError, "Cannot convert Infinity to Rational.",
+            TypeError, "Cannot convert Infinity to Fraction.",
             R.from_decimal, Decimal("inf"))
         self.assertRaisesMessage(
-            TypeError, "Cannot convert -Infinity to Rational.",
+            TypeError, "Cannot convert -Infinity to Fraction.",
             R.from_decimal, Decimal("-inf"))
         self.assertRaisesMessage(
-            TypeError, "Cannot convert NaN to Rational.",
+            TypeError, "Cannot convert NaN to Fraction.",
             R.from_decimal, Decimal("nan"))
         self.assertRaisesMessage(
-            TypeError, "Cannot convert sNaN to Rational.",
+            TypeError, "Cannot convert sNaN to Fraction.",
             R.from_decimal, Decimal("snan"))
 
     def testFromContinuedFraction(self):
@@ -316,7 +316,7 @@
         # Decimal refuses mixed comparisons.
         self.assertRaisesMessage(
             TypeError,
-            "unsupported operand type(s) for +: 'Rational' and 'Decimal'",
+            "unsupported operand type(s) for +: 'Fraction' and 'Decimal'",
             operator.add, R(3,11), Decimal('3.1415926'))
         self.assertNotEquals(R(5, 2), Decimal('2.5'))
 
@@ -378,7 +378,7 @@
         self.assertFalse(R(5, 2) == 2)
 
     def testStringification(self):
-        self.assertEquals("Rational(7,3)", repr(R(7, 3)))
+        self.assertEquals("Fraction(7,3)", repr(R(7, 3)))
         self.assertEquals("7/3", str(R(7, 3)))
         self.assertEquals("7", str(R(7, 1)))
 
@@ -421,7 +421,7 @@
         self.assertEqual(id(r), id(deepcopy(r)))
 
 def test_main():
-    run_unittest(RationalTest, GcdTest)
+    run_unittest(FractionTest, GcdTest)
 
 if __name__ == '__main__':
     test_main()