gh-98040: Remove just the imp module (#98573)

Python/import.c

@@ -594,11 +594,11 @@ _PyImport_ClearModulesByIndex(PyInterpreterState *interp)
 /*
     It may help to have a big picture view of what happens
     when an extension is loaded.  This includes when it is imported
-    for the first time or via imp.load_dynamic().
+    for the first time.
 
-    Here's a summary, using imp.load_dynamic() as the starting point:
+    Here's a summary, using importlib._boostrap._load() as a starting point.
 
-    1.  imp.load_dynamic() -> importlib._bootstrap._load()
+    1.  importlib._bootstrap._load()
     2.    _load():  acquire import lock
     3.    _load() -> importlib._bootstrap._load_unlocked()
     4.      _load_unlocked() -> importlib._bootstrap.module_from_spec()
@@ -3794,7 +3794,7 @@ _imp_source_hash_impl(PyObject *module, long key, Py_buffer *source)
 
 
 PyDoc_STRVAR(doc_imp,
-"(Extremely) low-level import machinery bits as used by importlib and imp.");
+"(Extremely) low-level import machinery bits as used by importlib.");
 
 static PyMethodDef imp_methods[] = {
     _IMP_EXTENSION_SUFFIXES_METHODDEF

Python/makeopcodetargets.py

@@ -7,24 +7,18 @@
 import sys
 
 
-try:
-    from importlib.machinery import SourceFileLoader
-except ImportError:
-    import imp
+# 2023-04-27(warsaw): Pre-Python 3.12, this would catch ImportErrors and try to
+# import imp, and then use imp.load_module().  The imp module was removed in
+# Python 3.12 (and long deprecated before that), and it's unclear under what
+# conditions this import will now fail, so the fallback was simply removed.
+from importlib.machinery import SourceFileLoader
 
-    def find_module(modname):
-        """Finds and returns a module in the local dist/checkout.
-        """
-        modpath = os.path.join(
-            os.path.dirname(os.path.dirname(__file__)), "Lib")
-        return imp.load_module(modname, *imp.find_module(modname, [modpath]))
-else:
-    def find_module(modname):
-        """Finds and returns a module in the local dist/checkout.
-        """
-        modpath = os.path.join(
-            os.path.dirname(os.path.dirname(__file__)), "Lib", modname + ".py")
-        return SourceFileLoader(modname, modpath).load_module()
+def find_module(modname):
+    """Finds and returns a module in the local dist/checkout.
+    """
+    modpath = os.path.join(
+        os.path.dirname(os.path.dirname(__file__)), "Lib", modname + ".py")
+    return SourceFileLoader(modname, modpath).load_module()
 
 
 def write_contents(f):

Python/pylifecycle.c

@@ -2173,10 +2173,9 @@ add_main_module(PyInterpreterState *interp)
         Py_DECREF(bimod);
     }
 
-    /* Main is a little special - imp.is_builtin("__main__") will return
-     * False, but BuiltinImporter is still the most appropriate initial
-     * setting for its __loader__ attribute. A more suitable value will
-     * be set if __main__ gets further initialized later in the startup
+    /* Main is a little special - BuiltinImporter is the most appropriate
+     * initial setting for its __loader__ attribute. A more suitable value
+     * will be set if __main__ gets further initialized later in the startup
      * process.
      */
     loader = _PyDict_GetItemStringWithError(d, "__loader__");

Python/stdlib_module_names.h

@@ -164,7 +164,6 @@ static const char* _Py_stdlib_module_names[] = {
 "idlelib",
 "imaplib",
 "imghdr",
-"imp",
 "importlib",
 "inspect",
 "io",