apply suggestions from code review

Author: SZeltaat

Doc/extending/extending.rst

@@ -77,12 +77,33 @@ the module and a copyright notice if you like).
 All user-visible symbols defined by :file:`Python.h` have a prefix of ``Py`` or
 ``PY``, except those defined in standard header files.
 
-For backward compatibility, :file:`!Python.h`
-includes ``<stdio.h>``, ``<string.h>``, ``<errno.h>``, and ``<stdlib.h>`` if
-:c:macro:`Py_LIMITED_API` is not defined or for limited C API version 3.10 and older.
-The ``<ctype.h>`` and ``<unistd.h>`` headers are also not included for limited
-C API version 3.13 and newer.
-
+For backward compatibility, :file:`Python.h` includes several standard header files.
+C extensions should include the standard headers that they use, and should not rely
+on these implicit includes.
+If using the limited C API version 3.13 or newer, the implicit includes are:
+
+* ``<assert.h>``
+* ``<intrin.h>`` (on Windows)
+* ``<inttypes.h>``
+* ``<limits.h>``
+* ``<math.h>``
+* ``<stdarg.h>``
+* ``<wchar.h>``
+* ``<sys/types.h>`` (if present)
+
+If :c:macro:`Py_LIMITED_API` is not defined, or is set to version 3.12 or older,
+the headers below are also included:
+
+* ``<ctype.h>``
+* ``<unistd.h>`` (on POSIX)
+
+If :c:macro:`Py_LIMITED_API` is not defined, or is set to version 3.10 or older,
+the headers below are also included:
+
+* ``<errno.h>``
+* ``<stdio.h>``
+* ``<stdlib.h>``
+* ``<string.h>``
 
 The next thing we add to our module file is the C function that will be called
 when the Python expression ``spam.system(string)`` is evaluated (we'll see

Include/Python.h

@@ -2,6 +2,10 @@
 // C extensions should only #include <Python.h>, and not include directly
 // the other Python header files included by <Python.h>.
 
+// Note: If the included standard headers change, please update the documentation
+// (including the documentation for C extensions) accordingly.
+
+
 #ifndef Py_PYTHON_H
 #define Py_PYTHON_H