gh-124502: Add PyUnicode_Equal() function (#124504)

Doc/c-api/unicode.rst

@@ -1438,6 +1438,31 @@ They all return ``NULL`` or ``-1`` if an exception occurs.
    This function returns ``-1`` upon failure, so one should call
    :c:func:`PyErr_Occurred` to check for errors.
 
+   .. seealso::
+
+      The :c:func:`PyUnicode_Equal` function.
+
+
+.. c:function:: int PyUnicode_Equal(PyObject *a, PyObject *b)
+
+   Test if two strings are equal:
+
+   * Return ``1`` if *a* is equal to *b*.
+   * Return ``0`` if *a* is not equal to *b*.
+   * Set a :exc:`TypeError` exception and return ``-1`` if *a* or *b* is not a
+     :class:`str` object.
+
+   The function always succeeds if *a* and *b* are :class:`str` objects.
+
+   The function works for :class:`str` subclasses, but does not honor custom
+   ``__eq__()`` method.
+
+   .. seealso::
+
+      The :c:func:`PyUnicode_Compare` function.
+
+   .. versionadded:: 3.14
+
 
 .. c:function:: int PyUnicode_EqualToUTF8AndSize(PyObject *unicode, const char *string, Py_ssize_t size)