Oops. Here are the new files. My apologies.

Include/boolobject.h

+/* Boolean object interface */
+
+typedef PyIntObject PyBoolObject;
+
+extern DL_IMPORT(PyTypeObject) PyBool_Type;
+
+#define PyBool_Check(x) ((x)->ob_type == &PyBool_Type)
+
+/* Py_False and Py_True are the only two bools in existence.
+Don't forget to apply Py_INCREF() when returning either!!! */
+
+/* Don't use these directly */
+extern DL_IMPORT(PyIntObject) _Py_ZeroStruct, _Py_TrueStruct;
+
+/* Use these macros */
+#define Py_False ((PyObject *) &_Py_ZeroStruct)
+#define Py_True ((PyObject *) &_Py_TrueStruct)
+
+/* Function to return a bool from a C long */
+PyObject *PyBool_FromLong(long);

Lib/test/test_bool.py

+# Test properties of bool promised by PEP 285
+
+from test_support import verbose, TestFailed, TESTFN, vereq
+
+def veris(a, b):
+    if a is not b:
+        raise TestFailed, "%r is %r" % (a, b)
+
+def verisnot(a, b):
+    if a is b:
+        raise TestFailed, "%r is %r" % (a, b)
+
+try:
+    class C(bool):
+        pass
+except TypeError:
+    pass
+else:
+    raise TestFailed, "bool should not be subclassable"
+
+try:
+    int.__new__(bool, 0)
+except TypeError:
+    pass
+else:
+    raise TestFailed, "should not be able to create new bool instances"
+
+vereq(int(False), 0)
+verisnot(int(False), False)
+vereq(int(True), 1)
+verisnot(int(True), True)
+
+vereq(+False, 0)
+verisnot(+False, False)
+vereq(-False, 0)
+verisnot(-False, False)
+vereq(abs(False), 0)
+verisnot(abs(False), False)
+vereq(+True, 1)
+verisnot(+True, True)
+vereq(-True, -1)
+vereq(abs(True), 1)
+verisnot(abs(True), True)
+vereq(~False, -1)
+vereq(~True, -2)
+
+vereq(False+2, 2)
+vereq(True+2, 3)
+vereq(2+False, 2)
+vereq(2+True, 3)
+
+vereq(False+False, 0)
+verisnot(False+False, False)
+vereq(False+True, 1)
+verisnot(False+True, True)
+vereq(True+False, 1)
+verisnot(True+False, True)
+vereq(True+True, 2)
+
+vereq(True-True, 0)
+verisnot(True-True, False)
+vereq(False-False, 0)
+verisnot(False-False, False)
+vereq(True-False, 1)
+verisnot(True-False, True)
+vereq(False-True, -1)
+
+vereq(True*1, 1)
+vereq(False*1, 0)
+verisnot(False*1, False)
+
+vereq(True/1, 1)
+verisnot(True/1, True)
+vereq(False/1, 0)
+verisnot(False/1, False)
+
+for b in False, True:
+    for i in 0, 1, 2:
+        vereq(b**i, int(b)**i)
+        verisnot(b**i, bool(int(b)**i))
+
+for a in False, True:
+    for b in False, True:
+        veris(a&b, bool(int(a)&int(b)))
+        veris(a|b, bool(int(a)|int(b)))
+        veris(a^b, bool(int(a)^int(b)))
+        vereq(a&int(b), int(a)&int(b))
+        verisnot(a&int(b), bool(int(a)&int(b)))
+        vereq(a|int(b), int(a)|int(b))
+        verisnot(a|int(b), bool(int(a)|int(b)))
+        vereq(a^int(b), int(a)^int(b))
+        verisnot(a^int(b), bool(int(a)^int(b)))
+        vereq(int(a)&b, int(a)&int(b))
+        verisnot(int(a)&b, bool(int(a)&int(b)))
+        vereq(int(a)|b, int(a)|int(b))
+        verisnot(int(a)|b, bool(int(a)|int(b)))
+        vereq(int(a)^b, int(a)^int(b))
+        verisnot(int(a)^b, bool(int(a)^int(b)))
+
+veris(1==1, True)
+veris(1==0, False)
+# XXX <, <=, >, >=, !=
+
+x = [1]
+veris(x is x, True)
+veris(x is not x, False)
+
+veris(1 in x, True)
+veris(0 in x, False)
+veris(1 not in x, False)
+veris(0 not in x, True)
+
+veris(not True, False)
+veris(not False, True)
+
+veris(bool(10), True)
+veris(bool(1), True)
+veris(bool(-1), True)
+veris(bool(0), False)
+veris(bool("hello"), True)
+veris(bool(""), False)
+
+veris(hasattr([], "append"), True)
+veris(hasattr([], "wobble"), False)
+
+veris(callable(len), True)
+veris(callable(1), False)
+
+veris(isinstance(True, bool), True)
+veris(isinstance(False, bool), True)
+veris(isinstance(True, int), True)
+veris(isinstance(False, int), True)
+veris(isinstance(1, bool), False)
+veris(isinstance(0, bool), False)
+
+veris(issubclass(bool, int), True)
+veris(issubclass(int, bool), False)
+
+veris({}.has_key(1), False)
+veris({1:1}.has_key(1), True)
+
+veris("xyz".endswith("z"), True)
+veris("xyz".endswith("x"), False)
+veris("xyz0123".isalnum(), True)
+veris("@#$%".isalnum(), False)
+veris("xyz".isalpha(), True)
+veris("@#$%".isalpha(), False)
+veris("0123".isdigit(), True)
+veris("xyz".isdigit(), False)
+veris("xyz".islower(), True)
+veris("XYZ".islower(), False)
+veris(" ".isspace(), True)
+veris("XYZ".isspace(), False)
+veris("X".istitle(), True)
+veris("x".istitle(), False)
+veris("XYZ".isupper(), True)
+veris("xyz".isupper(), False)
+veris("xyz".startswith("x"), True)
+veris("xyz".startswith("z"), False)
+
+veris(u"xyz".endswith(u"z"), True)
+veris(u"xyz".endswith(u"x"), False)
+veris(u"xyz0123".isalnum(), True)
+veris(u"@#$%".isalnum(), False)
+veris(u"xyz".isalpha(), True)
+veris(u"@#$%".isalpha(), False)
+veris(u"0123".isdecimal(), True)
+veris(u"xyz".isdecimal(), False)
+veris(u"0123".isdigit(), True)
+veris(u"xyz".isdigit(), False)
+veris(u"xyz".islower(), True)
+veris(u"XYZ".islower(), False)
+veris(u"0123".isnumeric(), True)
+veris(u"xyz".isnumeric(), False)
+veris(u" ".isspace(), True)
+veris(u"XYZ".isspace(), False)
+veris(u"X".istitle(), True)
+veris(u"x".istitle(), False)
+veris(u"XYZ".isupper(), True)
+veris(u"xyz".isupper(), False)
+veris(u"xyz".startswith(u"x"), True)
+veris(u"xyz".startswith(u"z"), False)
+
+f = file(TESTFN, "w")
+veris(f.closed, False)
+f.close()
+veris(f.closed, True)
+import os
+os.remove(TESTFN)
+
+import operator
+veris(operator.truth(0), False)
+veris(operator.truth(1), True)
+veris(operator.isCallable(0), False)
+veris(operator.isCallable(len), True)
+veris(operator.isNumberType(None), False)
+veris(operator.isNumberType(0), True)
+veris(operator.not_(1), False)
+veris(operator.not_(0), True)
+veris(operator.isSequenceType(0), False)
+veris(operator.isSequenceType([]), True)
+veris(operator.contains([], 1), False)
+veris(operator.contains([1], 1), True)
+veris(operator.isMappingType([]), False)
+veris(operator.isMappingType({}), True)
+veris(operator.lt(0, 0), False)
+veris(operator.lt(0, 1), True)
+
+import marshal
+veris(marshal.loads(marshal.dumps(True)), True)
+veris(marshal.loads(marshal.dumps(False)), False)
+
+import pickle
+veris(pickle.loads(pickle.dumps(True)), True)
+veris(pickle.loads(pickle.dumps(False)), False)
+
+import cPickle
+veris(cPickle.loads(cPickle.dumps(True)), True)
+veris(cPickle.loads(cPickle.dumps(False)), False)
+
+veris(pickle.loads(cPickle.dumps(True)), True)
+veris(pickle.loads(cPickle.dumps(False)), False)
+
+veris(cPickle.loads(pickle.dumps(True)), True)
+veris(cPickle.loads(pickle.dumps(False)), False)
+
+if verbose:
+    print "All OK"

Objects/boolobject.c

+/* Boolean type, a subtype of int */
+
+#include "Python.h"
+
+/* We need to define bool_print to override int_print */
+
+static int
+bool_print(PyBoolObject *self, FILE *fp, int flags)
+{
+	if (flags & Py_PRINT_RAW) {
+		if (self->ob_ival == 0)
+			fputs("False", fp);
+		else
+			fputs("True", fp);
+	}
+	else {
+		if (self->ob_ival == 0)
+			fputs("False", fp);
+		else
+			fputs("True", fp);
+	}
+	return 0;
+}
+
+/* We define bool_repr to return "False" or "True" */
+
+static PyObject *false_str = NULL;
+static PyObject *true_str = NULL;
+
+PyObject *
+bool_repr(PyBoolObject *self)
+{
+	PyObject *s;
+
+	if (self->ob_ival)
+		s = true_str ? true_str :
+			(true_str = PyString_InternFromString("True"));
+	else
+		s = false_str ? false_str :
+			(false_str = PyString_InternFromString("False"));
+	Py_XINCREF(s);
+	return s;
+}
+
+/* Function to return a bool from a C long */
+
+PyObject *PyBool_FromLong(long ok)
+{
+	PyObject *result;
+
+	if (ok)
+		result = Py_True;
+	else
+		result = Py_False;
+	Py_INCREF(result);
+	return result;
+}
+
+/* We define bool_new to always return either Py_True or Py_False */
+
+PyObject *
+bool_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
+{
+	static char *kwlist[] = {"x", 0};
+	PyObject *x;
+	long ok;
+
+	if (!PyArg_ParseTupleAndKeywords(args, kwds, "O:bool", kwlist, &x))
+		return NULL;
+	ok = PyObject_IsTrue(x);
+	if (ok < 0)
+		return NULL;
+	return PyBool_FromLong(ok);
+}
+
+/* Arithmetic operations redefined to return bool if both args are bool. */
+
+static PyObject *
+bool_and(PyObject *a, PyObject *b)
+{
+	if (!PyBool_Check(a) || !PyBool_Check(b))
+		return PyInt_Type.tp_as_number->nb_and(a, b);
+	return PyBool_FromLong(
+		((PyBoolObject *)a)->ob_ival & ((PyBoolObject *)b)->ob_ival);
+}
+
+static PyObject *
+bool_or(PyObject *a, PyObject *b)
+{
+	if (!PyBool_Check(a) || !PyBool_Check(b))
+		return PyInt_Type.tp_as_number->nb_or(a, b);
+	return PyBool_FromLong(
+		((PyBoolObject *)a)->ob_ival | ((PyBoolObject *)b)->ob_ival);
+}
+
+static PyObject *
+bool_xor(PyObject *a, PyObject *b)
+{
+	if (!PyBool_Check(a) || !PyBool_Check(b))
+		return PyInt_Type.tp_as_number->nb_xor(a, b);
+	return PyBool_FromLong(
+		((PyBoolObject *)a)->ob_ival ^ ((PyBoolObject *)b)->ob_ival);
+}
+
+/* Doc string */
+
+static char bool_doc[] =
+"bool(x) -> bool\n\
+\n\
+Returns True when the argument x is true, False otherwise.\n\
+The builtins True and False are the only two instances of the class bool.\n\
+The class bool is a subclass of the class int, and cannot be subclassed.";
+
+/* Arithmetic methods -- only so we can override &, |, ^. */
+
+static PyNumberMethods bool_as_number = {
+	0,	/*nb_add*/
+	0,	/*nb_subtract*/
+	0,	/*nb_multiply*/
+	0, /*nb_divide*/
+	0,	/*nb_remainder*/
+	0,	/*nb_divmod*/
+	0,	/*nb_power*/
+	0,	/*nb_negative*/
+	0,	/*nb_positive*/
+	0,	/*nb_absolute*/
+	0,	/*nb_nonzero*/
+	0,	/*nb_invert*/
+	0,	/*nb_lshift*/
+	0,	/*nb_rshift*/
+	(binaryfunc)bool_and,	/*nb_and*/
+	(binaryfunc)bool_xor,	/*nb_xor*/
+	(binaryfunc)bool_or,	/*nb_or*/
+	0,		/*nb_coerce*/
+	0,	/*nb_int*/
+	0,	/*nb_long*/
+	0,	/*nb_float*/
+	0,	/*nb_oct*/
+	0, 	/*nb_hex*/
+	0,			/*nb_inplace_add*/
+	0,			/*nb_inplace_subtract*/
+	0,			/*nb_inplace_multiply*/
+	0,			/*nb_inplace_divide*/
+	0,			/*nb_inplace_remainder*/
+	0,			/*nb_inplace_power*/
+	0,			/*nb_inplace_lshift*/
+	0,			/*nb_inplace_rshift*/
+	0,			/*nb_inplace_and*/
+	0,			/*nb_inplace_xor*/
+	0,			/*nb_inplace_or*/
+	0,	/* nb_floor_divide */
+	0,	/* nb_true_divide */
+	0,			/* nb_inplace_floor_divide */
+	0,			/* nb_inplace_true_divide */
+};
+
+/* The type object for bool.  Note that this cannot be subclassed! */
+
+PyTypeObject PyBool_Type = {
+	PyObject_HEAD_INIT(&PyType_Type)
+	0,
+	"bool",
+	sizeof(PyIntObject),
+	0,
+	0,					/* tp_dealloc */
+	(printfunc)bool_print,			/* tp_print */
+	0,					/* tp_getattr */
+	0,					/* tp_setattr */
+	0,					/* tp_compare */
+	(reprfunc)bool_repr,			/* tp_repr */
+	&bool_as_number,			/* tp_as_number */
+	0,					/* tp_as_sequence */
+	0,					/* tp_as_mapping */
+	0,					/* tp_hash */
+        0,					/* tp_call */
+        (reprfunc)bool_repr,			/* tp_str */
+	0,					/* tp_getattro */
+	0,					/* tp_setattro */
+	0,					/* tp_as_buffer */
+	Py_TPFLAGS_DEFAULT | Py_TPFLAGS_CHECKTYPES, /* tp_flags */
+	bool_doc,				/* tp_doc */
+	0,					/* tp_traverse */
+	0,					/* tp_clear */
+	0,					/* tp_richcompare */
+	0,					/* tp_weaklistoffset */
+	0,					/* tp_iter */
+	0,					/* tp_iternext */
+	0,					/* tp_methods */
+	0,					/* tp_members */
+	0,					/* tp_getset */
+	&PyInt_Type,				/* tp_base */
+	0,					/* tp_dict */
+	0,					/* tp_descr_get */
+	0,					/* tp_descr_set */
+	0,					/* tp_dictoffset */
+	0,					/* tp_init */
+	0,					/* tp_alloc */
+	bool_new,				/* tp_new */
+};
+
+/* The objects representing bool values False and True */
+
+/* Named Zero for link-level compatibility */
+PyIntObject _Py_ZeroStruct = {
+	PyObject_HEAD_INIT(&PyBool_Type)
+	0
+};
+
+PyIntObject _Py_TrueStruct = {
+	PyObject_HEAD_INIT(&PyBool_Type)
+	1
+};