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+:mod:`fractions` --- Rational numbers
+====================================
+
+.. module:: fractions
+ :synopsis: Rational numbers.
+.. moduleauthor:: Jeffrey Yasskin <jyasskin at gmail.com>
+.. sectionauthor:: Jeffrey Yasskin <jyasskin at gmail.com>
+.. versionadded:: 2.6
+
+
+The :mod:`fractions` module defines an immutable, infinite-precision
+Fraction number class.
+
+
+.. class:: Fraction(numerator=0, denominator=1)
+ Fraction(other_fraction)
+ Fraction(string)
+
+ The first version requires that *numerator* and *denominator* are
+ instances of :class:`numbers.Integral` and returns a new
+ ``Fraction`` representing ``numerator/denominator``. If
+ *denominator* is :const:`0`, raises a :exc:`ZeroDivisionError`. The
+ second version requires that *other_fraction* is an instance of
+ :class:`numbers.Rational` and returns an instance of
+ :class:`Fraction` with the same value. The third version expects a
+ string of the form ``[-+]?[0-9]+(/[0-9]+)?``, optionally surrounded
+ by spaces.
+
+ Implements all of the methods and operations from
+ :class:`numbers.Rational` and is immutable and hashable.
+
+
+.. method:: Fraction.from_float(flt)
+
+ This classmethod constructs a :class:`Fraction` representing the
+ exact value of *flt*, which must be a :class:`float`. Beware that
+ ``Fraction.from_float(0.3)`` is not the same value as ``Fraction(3,
+ 10)``
+
+
+.. method:: Fraction.from_decimal(dec)
+
+ This classmethod constructs a :class:`Fraction` representing the
+ exact value of *dec*, which must be a
+ :class:`decimal.Decimal`.
+
+
+.. method:: Fraction.__floor__()
+
+ Returns the greatest :class:`int` ``<= self``. Will be accessible
+ through :func:`math.floor` in Py3k.
+
+
+.. method:: Fraction.__ceil__()
+
+ Returns the least :class:`int` ``>= self``. Will be accessible
+ through :func:`math.ceil` in Py3k.
+
+
+.. method:: Fraction.__round__()
+ Fraction.__round__(ndigits)
+
+ The first version returns the nearest :class:`int` to ``self``,
+ rounding half to even. The second version rounds ``self`` to the
+ nearest multiple of ``Fraction(1, 10**ndigits)`` (logically, if
+ ``ndigits`` is negative), again rounding half toward even. Will be
+ accessible through :func:`round` in Py3k.
+
+
+.. seealso::
+
+ Module :mod:`numbers`
+ The abstract base classes making up the numeric tower.
+