gh-103326: Remove `Python/importlib.h` (GH-103331)

Co-authored-by: Brett Cannon <brett@python.org>
Co-authored-by: Hugo van Kemenade <hugovk@users.noreply.github.com>

.github/CODEOWNERS

@@ -61,11 +61,7 @@ Python/traceback.c            @iritkatriel
 /Tools/build/parse_html5_entities.py   @ezio-melotti
 
 # Import (including importlib).
-# Ignoring importlib.h so as to not get flagged on
-# all pull requests that change the emitted
-# bytecode.
-**/*import*.c                 @brettcannon @encukou @ericsnowcurrently @ncoghlan @warsaw
-**/*import*.py                @brettcannon @encukou @ericsnowcurrently @ncoghlan @warsaw
+**/*import*                   @brettcannon @encukou @ericsnowcurrently @ncoghlan @warsaw
 **/*importlib/resources/*      @jaraco @warsaw @FFY00
 **/importlib/metadata/*       @jaraco @warsaw
 

Programs/_freeze_module.c

@@ -1,6 +1,5 @@
 /* This is built as a stand-alone executable by the Makefile, and helps turn
-   modules into frozen modules (like Lib/importlib/_bootstrap.py
-   into Python/importlib.h).
+   modules into frozen modules.
 
    This is used directly by Tools/build/freeze_modules.py, and indirectly by "make regen-frozen".
 

Tools/c-analyzer/cpython/_parser.py

@@ -328,7 +328,6 @@ MAX_SIZES = {
     _abs('Python/frozen_modules/*.h'): (20_000, 500),
     _abs('Python/opcode_targets.h'): (10_000, 500),
     _abs('Python/stdlib_module_names.h'): (5_000, 500),
-    _abs('Python/importlib.h'): (200_000, 5000),
 
     # These large files are currently ignored (see above).
     _abs('Modules/_ssl_data.h'): (80_000, 10_000),

configure

@@ -3104,7 +3104,6 @@ if test "$srcdir" != . -a "$srcdir" != "$(pwd)"; then
     # resources get picked up before their $srcdir counterparts.
     #   Objects/ -> typeslots.inc
     #   Include/ -> Python.h
-    #   Python/  -> importlib.h
     # (A side effect of this is that these resources will automatically be
     #  regenerated when building out-of-tree, regardless of whether or not
     #  the $srcdir counterpart is up-to-date.  This is an acceptable trade

configure.ac

@@ -97,7 +97,6 @@ if test "$srcdir" != . -a "$srcdir" != "$(pwd)"; then
     # resources get picked up before their $srcdir counterparts.
     #   Objects/ -> typeslots.inc
     #   Include/ -> Python.h
-    #   Python/  -> importlib.h
     # (A side effect of this is that these resources will automatically be
     #  regenerated when building out-of-tree, regardless of whether or not
     #  the $srcdir counterpart is up-to-date.  This is an acceptable trade