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+:mod:`rational` --- Rational numbers
+====================================
+
+.. module:: rational
+   :synopsis: Rational numbers.
+.. moduleauthor:: Jeffrey Yasskin <jyasskin at gmail.com>
+.. sectionauthor:: Jeffrey Yasskin <jyasskin at gmail.com>
+.. versionadded:: 2.6
+
+
+The :mod:`rational` module defines an immutable, infinite-precision
+Rational number class.
+
+
+.. class:: Rational(numerator=0, denominator=1)
+           Rational(other_rational)
+
+   The first version requires that *numerator* and *denominator* are
+   instances of :class:`numbers.Integral` and returns a new
+   ``Rational`` representing ``numerator/denominator``. If
+   *denominator* is :const:`0`, raises a :exc:`ZeroDivisionError`. The
+   second version requires that *other_rational* is an instance of
+   :class:`numbers.Rational` and returns an instance of
+   :class:`Rational` with the same value.
+
+   Implements all of the methods and operations from
+   :class:`numbers.Rational` and is hashable.
+
+
+.. method:: Rational.from_float(flt)
+
+   This classmethod constructs a :class:`Rational` representing the
+   exact value of *flt*, which must be a :class:`float`. Beware that
+   ``Rational.from_float(0.3)`` is not the same value as ``Rational(3,
+   10)``
+
+
+.. method:: Rational.__floor__()
+
+   Returns the greatest :class:`int` ``<= self``. Will be accessible
+   through :func:`math.floor` in Py3k.
+
+
+.. method:: Rational.__ceil__()
+
+   Returns the least :class:`int` ``>= self``. Will be accessible
+   through :func:`math.ceil` in Py3k.
+
+
+.. method:: Rational.__round__()
+            Rational.__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 ``Rational(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.
+