Revert "bpo-26680: Incorporate is_integer in all built-in and standard library numeric types (GH-6121)" (GH-22584)

This reverts commit 58a7da9e125422323f79c4ee95ac5549989d8162.
diff --git a/Doc/library/numbers.rst b/Doc/library/numbers.rst
index 5d49f5e..1b59495 100644
--- a/Doc/library/numbers.rst
+++ b/Doc/library/numbers.rst
@@ -49,30 +49,19 @@
    numbers.
 
    In short, those are: a conversion to :class:`float`, :func:`math.trunc`,
-   :func:`round`, :func:`math.floor`, :func:`math.ceil`, :func:`divmod`,
-   :func:`~Real.is_integer`, ``//``, ``%``, ``<``, ``<=``, ``>``, and ``>=``.
+   :func:`round`, :func:`math.floor`, :func:`math.ceil`, :func:`divmod`, ``//``,
+   ``%``, ``<``, ``<=``, ``>``, and ``>=``.
 
    Real also provides defaults for :func:`complex`, :attr:`~Complex.real`,
    :attr:`~Complex.imag`, and :meth:`~Complex.conjugate`.
 
-   .. method:: is_integer()
-
-      Returns :const:`True` if this number has a finite and integral value,
-      otherwise :const:`False`.  This is a default implementation which
-      relies on successful conversion to :class:`int`. It may be overridden
-      in subclasses (such as it is in :class:`float`) for better performance,
-      or to handle special values such as NaN which are not
-      convertible to :class:`int`.
-
-      .. versionadded:: 3.10
-
 
 .. class:: Rational
 
    Subtypes :class:`Real` and adds
    :attr:`~Rational.numerator` and :attr:`~Rational.denominator` properties, which
-   should be in lowest terms. With these, it provides defaults for
-   :func:`float` and :func:`~Real.is_integer`.
+   should be in lowest terms. With these, it provides a default for
+   :func:`float`.
 
    .. attribute:: numerator
 
@@ -86,10 +75,9 @@
 .. class:: Integral
 
    Subtypes :class:`Rational` and adds a conversion to :class:`int`.  Provides
-   defaults for :func:`float`, :attr:`~Rational.numerator`,
-   :attr:`~Rational.denominator`, and :func:`~Real.is_integer`.  Adds abstract
-   methods for ``**`` and bit-string operations: ``<<``, ``>>``, ``&``, ``^``,
-   ``|``, ``~``.
+   defaults for :func:`float`, :attr:`~Rational.numerator`, and
+   :attr:`~Rational.denominator`.  Adds abstract methods for ``**`` and
+   bit-string operations: ``<<``, ``>>``, ``&``, ``^``, ``|``, ``~``.
 
 
 Notes for type implementors