Merge branch 'main' into docs-floating-point

Doc/library/fractions.rst

@@ -26,12 +26,17 @@ another rational number, or from a string.
    The first version requires that *numerator* and *denominator* are instances
    of :class:`numbers.Rational` and returns a new :class:`Fraction` instance
    with value ``numerator/denominator``. If *denominator* is ``0``, it
-   raises a :exc:`ZeroDivisionError`. The second version requires that
-   *other_fraction* is an instance of :class:`numbers.Rational` and returns a
-   :class:`Fraction` instance with the same value.  The next two versions accept
-   either a :class:`float` or a :class:`decimal.Decimal` instance, and return a
-   :class:`Fraction` instance with exactly the same value.  Note that due to the
-   usual issues with binary floating point (see :ref:`tut-fp-issues`), the
+   raises a :exc:`ZeroDivisionError`.
+
+   The second version requires that *number* is an instance of
+   :class:`numbers.Rational` or has the :meth:`!as_integer_ratio` method
+   (this includes :class:`float` and :class:`decimal.Decimal`).
+   It returns a :class:`Fraction` instance with exactly the same value.
+   Assumed, that the :meth:`!as_integer_ratio` method returns a pair
+   of coprime integers and last one is positive.
+   Note that due to the
+   usual issues with binary 
+   point (see :ref:`tut-fp-issues`), the
    argument to ``Fraction(1.1)`` is not exactly equal to 11/10, and so
    ``Fraction(1.1)`` does *not* return ``Fraction(11, 10)`` as one might expect.
    (But see the documentation for the :meth:`limit_denominator` method below.)