Index: Lib/test/test_zlib.py
===================================================================
--- Lib/test/test_zlib.py	(revision 66222)
+++ Lib/test/test_zlib.py	(working copy)
@@ -152,7 +152,11 @@
         bufs.append(co.flush())
         combuf = b''.join(bufs)
 
-        self.assertEqual(data, zlib.decompress(combuf))
+        decombuf = zlib.decompress(combuf)
+        # Test type of return value
+        self.assertEqual(type(decombuf), bytes)
+        
+        self.assertEqual(data, decombuf)
 
         dco = zlib.decompressobj()
         bufs = []
@@ -348,7 +352,9 @@
             # Test copying a decompression object
             data = HAMLET_SCENE
             comp = zlib.compress(data)
-
+            # Test type of return value
+            self.assertEqual(type(comp), bytes)
+            
             d0 = zlib.decompressobj()
             bufs0 = []
             bufs0.append(d0.decompress(comp[:32]))
Index: Modules/zipimport.c
===================================================================
--- Modules/zipimport.c	(revision 66222)
+++ Modules/zipimport.c	(working copy)
@@ -467,7 +467,7 @@
 	toc_entry = PyDict_GetItemString(self->files, path);
 	if (toc_entry != NULL) {
 		PyObject *bytes = get_data(_PyUnicode_AsString(self->archive), toc_entry);
-		PyObject *res = PyUnicode_FromString(PyByteArray_AsString(bytes));
+		PyObject *res = PyUnicode_FromString(PyBytes_AsString(bytes));
 		Py_XDECREF(bytes);
 		return res;
 	}
@@ -836,13 +836,13 @@
 	bytes_size = compress == 0 ? data_size : data_size + 1;
 	if (bytes_size == 0)
 		bytes_size++;
-	raw_data = PyByteArray_FromStringAndSize((char *)NULL, bytes_size);
+	raw_data = PyBytes_FromStringAndSize((char *)NULL, bytes_size);
 					     
 	if (raw_data == NULL) {
 		fclose(fp);
 		return NULL;
 	}
-	buf = PyByteArray_AsString(raw_data);
+	buf = PyBytes_AsString(raw_data);
 
 	err = fseek(fp, file_offset, 0);
 	if (err == 0)
@@ -862,7 +862,7 @@
 	buf[data_size] = '\0';
 
 	if (compress == 0) {  /* data is not compressed */
-		data = PyByteArray_FromStringAndSize(buf, data_size);
+		data = PyBytes_FromStringAndSize(buf, data_size);
 		Py_DECREF(raw_data);
 		return data;
 	}
@@ -903,8 +903,8 @@
 unmarshal_code(char *pathname, PyObject *data, time_t mtime)
 {
 	PyObject *code;
-	char *buf = PyByteArray_AsString(data);
-	Py_ssize_t size = PyByteArray_Size(data);
+	char *buf = PyBytes_AsString(data);
+	Py_ssize_t size = PyBytes_Size(data);
 
 	if (size <= 9) {
 		PyErr_SetString(ZipImportError,
@@ -949,16 +949,16 @@
 static PyObject *
 normalize_line_endings(PyObject *source)
 {
-	char *buf, *q, *p = PyByteArray_AsString(source);
+	char *buf, *q, *p = PyBytes_AsString(source);
 	PyObject *fixed_source;
 	int len = 0;
 
 	if (!p) {
-		return PyByteArray_FromStringAndSize("\n\0", 2);
+		return PyBytes_FromStringAndSize("\n\0", 2);
 	}
 
 	/* one char extra for trailing \n and one for terminating \0 */
-	buf = (char *)PyMem_Malloc(PyByteArray_Size(source) + 2);
+	buf = (char *)PyMem_Malloc(PyBytes_Size(source) + 2);
 	if (buf == NULL) {
 		PyErr_SetString(PyExc_MemoryError,
 				"zipimport: no memory to allocate "
@@ -978,7 +978,7 @@
 	}
 	*q++ = '\n';  /* add trailing \n */
 	*q = '\0';
-	fixed_source = PyByteArray_FromStringAndSize(buf, len + 2);
+	fixed_source = PyBytes_FromStringAndSize(buf, len + 2);
 	PyMem_Free(buf);
 	return fixed_source;
 }
@@ -994,7 +994,7 @@
 	if (fixed_source == NULL)
 		return NULL;
 
-	code = Py_CompileString(PyByteArray_AsString(fixed_source), pathname,
+	code = Py_CompileString(PyBytes_AsString(fixed_source), pathname,
 				Py_file_input);
 	Py_DECREF(fixed_source);
 	return code;
Index: Modules/zlibmodule.c
===================================================================
--- Modules/zlibmodule.c	(revision 66222)
+++ Modules/zlibmodule.c	(working copy)
@@ -178,7 +178,7 @@
 
     err=deflateEnd(&zst);
     if (err == Z_OK)
-	ReturnVal = PyByteArray_FromStringAndSize((char *)output,
+	ReturnVal = PyBytes_FromStringAndSize((char *)output,
                                               zst.total_out);
     else
 	zlib_error(zst, err, "while finishing compression");
@@ -219,14 +219,14 @@
     zst.avail_in = length;
     zst.avail_out = r_strlen;
 
-    if (!(result_str = PyByteArray_FromStringAndSize(NULL, r_strlen))) {
+    if (!(result_str = PyBytes_FromStringAndSize(NULL, r_strlen))) {
 	PyBuffer_Release(&pinput);
 	return NULL;
     }
 
     zst.zalloc = (alloc_func)NULL;
     zst.zfree = (free_func)Z_NULL;
-    zst.next_out = (Byte *)PyByteArray_AS_STRING(result_str);
+    zst.next_out = (Byte *)PyBytes_AS_STRING(result_str);
     zst.next_in = (Byte *)input;
     err = inflateInit2(&zst, wsize);
 
@@ -266,12 +266,12 @@
 	    /* fall through */
 	case(Z_OK):
 	    /* need more memory */
-	    if (PyByteArray_Resize(result_str, r_strlen << 1) < 0) {
+	    if (_PyBytes_Resize(&result_str, r_strlen << 1) < 0) {
 		inflateEnd(&zst);
 		goto error;
 	    }
 	    zst.next_out =
-                (unsigned char *)PyByteArray_AS_STRING(result_str) + r_strlen;
+                (unsigned char *)PyBytes_AS_STRING(result_str) + r_strlen;
 	    zst.avail_out = r_strlen;
 	    r_strlen = r_strlen << 1;
 	    break;
@@ -288,7 +288,7 @@
 	goto error;
     }
 
-    if (PyByteArray_Resize(result_str, zst.total_out) < 0)
+    if (_PyBytes_Resize(&result_str, zst.total_out) < 0)
         goto error;
 
     PyBuffer_Release(&pinput);
@@ -417,7 +417,7 @@
     input = pinput.buf;
     inplen = pinput.len;
 
-    if (!(RetVal = PyByteArray_FromStringAndSize(NULL, length))) {
+    if (!(RetVal = PyBytes_FromStringAndSize(NULL, length))) {
 	PyBuffer_Release(&pinput);
 	return NULL;
     }
@@ -428,7 +428,7 @@
     self->zst.avail_in = inplen;
     self->zst.next_in = input;
     self->zst.avail_out = length;
-    self->zst.next_out = (unsigned char *)PyByteArray_AS_STRING(RetVal);
+    self->zst.next_out = (unsigned char *)PyBytes_AS_STRING(RetVal);
 
     Py_BEGIN_ALLOW_THREADS
     err = deflate(&(self->zst), Z_NO_FLUSH);
@@ -437,13 +437,13 @@
     /* while Z_OK and the output buffer is full, there might be more output,
        so extend the output buffer and try again */
     while (err == Z_OK && self->zst.avail_out == 0) {
-	if (PyByteArray_Resize(RetVal, length << 1) < 0) {
+	if (_PyBytes_Resize(&RetVal, length << 1) < 0) {
             Py_DECREF(RetVal);
             RetVal = NULL;
 	    goto error;
         }
 	self->zst.next_out =
-            (unsigned char *)PyByteArray_AS_STRING(RetVal) + length;
+            (unsigned char *)PyBytes_AS_STRING(RetVal) + length;
 	self->zst.avail_out = length;
 	length = length << 1;
 
@@ -462,7 +462,7 @@
 	RetVal = NULL;
 	goto error;
     }
-    if (PyByteArray_Resize(RetVal, self->zst.total_out - start_total_out) < 0) {
+    if (_PyBytes_Resize(&RetVal, self->zst.total_out - start_total_out) < 0) {
         Py_DECREF(RetVal);
         RetVal = NULL;
     }
@@ -509,7 +509,7 @@
     /* limit amount of data allocated to max_length */
     if (max_length && length > max_length)
 	length = max_length;
-    if (!(RetVal = PyByteArray_FromStringAndSize(NULL, length))) {
+    if (!(RetVal = PyBytes_FromStringAndSize(NULL, length))) {
 	PyBuffer_Release(&pinput);
 	return NULL;
     }
@@ -520,7 +520,7 @@
     self->zst.avail_in = inplen;
     self->zst.next_in = input;
     self->zst.avail_out = length;
-    self->zst.next_out = (unsigned char *)PyByteArray_AS_STRING(RetVal);
+    self->zst.next_out = (unsigned char *)PyBytes_AS_STRING(RetVal);
 
     Py_BEGIN_ALLOW_THREADS
     err = inflate(&(self->zst), Z_SYNC_FLUSH);
@@ -542,13 +542,13 @@
 	if (max_length && length > max_length)
 	    length = max_length;
 
-	if (PyByteArray_Resize(RetVal, length) < 0) {
+	if (_PyBytes_Resize(&RetVal, length) < 0) {
             Py_DECREF(RetVal);
             RetVal = NULL;
 	    goto error;
         }
 	self->zst.next_out =
-            (unsigned char *)PyByteArray_AS_STRING(RetVal) + old_length;
+            (unsigned char *)PyBytes_AS_STRING(RetVal) + old_length;
 	self->zst.avail_out = length - old_length;
 
 	Py_BEGIN_ALLOW_THREADS
@@ -594,7 +594,7 @@
 	goto error;
     }
 
-    if (PyByteArray_Resize(RetVal, self->zst.total_out - start_total_out) < 0) {
+    if (_PyBytes_Resize(&RetVal, self->zst.total_out - start_total_out) < 0) {
         Py_DECREF(RetVal);
         RetVal = NULL;
     }
@@ -627,10 +627,10 @@
     /* Flushing with Z_NO_FLUSH is a no-op, so there's no point in
        doing any work at all; just return an empty string. */
     if (flushmode == Z_NO_FLUSH) {
-	return PyByteArray_FromStringAndSize(NULL, 0);
+	return PyBytes_FromStringAndSize(NULL, 0);
     }
 
-    if (!(RetVal = PyByteArray_FromStringAndSize(NULL, length)))
+    if (!(RetVal = PyBytes_FromStringAndSize(NULL, length)))
 	return NULL;
 
     ENTER_ZLIB
@@ -638,7 +638,7 @@
     start_total_out = self->zst.total_out;
     self->zst.avail_in = 0;
     self->zst.avail_out = length;
-    self->zst.next_out = (unsigned char *)PyByteArray_AS_STRING(RetVal);
+    self->zst.next_out = (unsigned char *)PyBytes_AS_STRING(RetVal);
 
     Py_BEGIN_ALLOW_THREADS
     err = deflate(&(self->zst), flushmode);
@@ -647,13 +647,13 @@
     /* while Z_OK and the output buffer is full, there might be more output,
        so extend the output buffer and try again */
     while (err == Z_OK && self->zst.avail_out == 0) {
-	if (PyByteArray_Resize(RetVal, length << 1) < 0) {
+	if (_PyBytes_Resize(&RetVal, length << 1) < 0) {
             Py_DECREF(RetVal);
             RetVal = NULL;
 	    goto error;
         }
 	self->zst.next_out =
-            (unsigned char *)PyByteArray_AS_STRING(RetVal) + length;
+            (unsigned char *)PyBytes_AS_STRING(RetVal) + length;
 	self->zst.avail_out = length;
 	length = length << 1;
 
@@ -687,7 +687,7 @@
 	goto error;
     }
 
-    if (PyByteArray_Resize(RetVal, self->zst.total_out - start_total_out) < 0) {
+    if (_PyBytes_Resize(&RetVal, self->zst.total_out - start_total_out) < 0) {
         Py_DECREF(RetVal);
         RetVal = NULL;
     }
@@ -822,7 +822,7 @@
 	PyErr_SetString(PyExc_ValueError, "length must be greater than zero");
 	return NULL;
     }
-    if (!(retval = PyByteArray_FromStringAndSize(NULL, length)))
+    if (!(retval = PyBytes_FromStringAndSize(NULL, length)))
 	return NULL;
 
 
@@ -830,7 +830,7 @@
 
     start_total_out = self->zst.total_out;
     self->zst.avail_out = length;
-    self->zst.next_out = (Byte *)PyByteArray_AS_STRING(retval);
+    self->zst.next_out = (Byte *)PyBytes_AS_STRING(retval);
 
     Py_BEGIN_ALLOW_THREADS
     err = inflate(&(self->zst), Z_FINISH);
@@ -839,12 +839,12 @@
     /* while Z_OK and the output buffer is full, there might be more output,
        so extend the output buffer and try again */
     while ((err == Z_OK || err == Z_BUF_ERROR) && self->zst.avail_out == 0) {
-	if (PyByteArray_Resize(retval, length << 1) < 0) {
+	if (_PyBytes_Resize(&retval, length << 1) < 0) {
             Py_DECREF(retval);
             retval = NULL;
 	    goto error;
         }
-	self->zst.next_out = (Byte *)PyByteArray_AS_STRING(retval) + length;
+	self->zst.next_out = (Byte *)PyBytes_AS_STRING(retval) + length;
 	self->zst.avail_out = length;
 	length = length << 1;
 
@@ -866,7 +866,7 @@
 	    goto error;
 	}
     }
-    if (PyByteArray_Resize(retval, self->zst.total_out - start_total_out) < 0) {
+    if (_PyBytes_Resize(&retval, self->zst.total_out - start_total_out) < 0) {
         Py_DECREF(retval);
         retval = NULL;
     }