diff --git a/Lib/shutil.py b/Lib/shutil.py
index 8ad0c64..f3a31a4 100644
--- a/Lib/shutil.py
+++ b/Lib/shutil.py
@@ -147,8 +147,8 @@
         return set(ignored_names)
     return _ignore_patterns
 
-def copytree(src, dst, symlinks=False, ignore=None):
-    """Recursively copy a directory tree using copy2().
+def copytree(src, dst, symlinks=False, ignore=None, copy_function=copy2):
+    """Recursively copy a directory tree.
 
     The destination directory must not already exist.
     If exception(s) occur, an Error is raised with a list of reasons.
@@ -170,7 +170,10 @@
     list of names relative to the `src` directory that should
     not be copied.
 
-    XXX Consider this example code rather than the ultimate tool.
+    The optional copy_function argument is a callable that will be used
+    to copy each file. It will be called with the source path and the
+    destination path as arguments. By default, copy2() is used, but any
+    function that supports the same signature (like copy()) can be used.
 
     """
     names = os.listdir(src)
@@ -191,10 +194,10 @@
                 linkto = os.readlink(srcname)
                 os.symlink(linkto, dstname)
             elif os.path.isdir(srcname):
-                copytree(srcname, dstname, symlinks, ignore)
+                copytree(srcname, dstname, symlinks, ignore, copy_function)
             else:
                 # Will raise a SpecialFileError for unsupported file types
-                copy2(srcname, dstname)
+                copy_function(srcname, dstname)
         # catch the Error from the recursive copytree so that we can
         # continue with other files
         except Error as err:
diff --git a/Lib/test/test_shutil.py b/Lib/test/test_shutil.py
index 3faa95e..dfa6f9f 100644
--- a/Lib/test/test_shutil.py
+++ b/Lib/test/test_shutil.py
@@ -74,6 +74,7 @@
         d = tempfile.mkdtemp()
         self.tempdirs.append(d)
         return d
+
     def test_rmtree_errors(self):
         # filename is guaranteed not to exist
         filename = tempfile.mktemp()
@@ -140,11 +141,12 @@
         self.assertRaises(OSError, shutil.rmtree, path)
         os.remove(path)
 
+    def _write_data(self, path, data):
+        f = open(path, "w")
+        f.write(data)
+        f.close()
+
     def test_copytree_simple(self):
-        def write_data(path, data):
-            f = open(path, "w")
-            f.write(data)
-            f.close()
 
         def read_data(path):
             f = open(path)
@@ -154,11 +156,9 @@
 
         src_dir = tempfile.mkdtemp()
         dst_dir = os.path.join(tempfile.mkdtemp(), 'destination')
-
-        write_data(os.path.join(src_dir, 'test.txt'), '123')
-
+        self._write_data(os.path.join(src_dir, 'test.txt'), '123')
         os.mkdir(os.path.join(src_dir, 'test_dir'))
-        write_data(os.path.join(src_dir, 'test_dir', 'test.txt'), '456')
+        self._write_data(os.path.join(src_dir, 'test_dir', 'test.txt'), '456')
 
         try:
             shutil.copytree(src_dir, dst_dir)
@@ -187,11 +187,6 @@
 
     def test_copytree_with_exclude(self):
 
-        def write_data(path, data):
-            f = open(path, "w")
-            f.write(data)
-            f.close()
-
         def read_data(path):
             f = open(path)
             data = f.read()
@@ -204,16 +199,18 @@
         src_dir = tempfile.mkdtemp()
         try:
             dst_dir = join(tempfile.mkdtemp(), 'destination')
-            write_data(join(src_dir, 'test.txt'), '123')
-            write_data(join(src_dir, 'test.tmp'), '123')
+            self._write_data(join(src_dir, 'test.txt'), '123')
+            self._write_data(join(src_dir, 'test.tmp'), '123')
             os.mkdir(join(src_dir, 'test_dir'))
-            write_data(join(src_dir, 'test_dir', 'test.txt'), '456')
+            self._write_data(join(src_dir, 'test_dir', 'test.txt'), '456')
             os.mkdir(join(src_dir, 'test_dir2'))
-            write_data(join(src_dir, 'test_dir2', 'test.txt'), '456')
+            self._write_data(join(src_dir, 'test_dir2', 'test.txt'), '456')
             os.mkdir(join(src_dir, 'test_dir2', 'subdir'))
             os.mkdir(join(src_dir, 'test_dir2', 'subdir2'))
-            write_data(join(src_dir, 'test_dir2', 'subdir', 'test.txt'), '456')
-            write_data(join(src_dir, 'test_dir2', 'subdir2', 'test.py'), '456')
+            self._write_data(join(src_dir, 'test_dir2', 'subdir', 'test.txt'),
+                             '456')
+            self._write_data(join(src_dir, 'test_dir2', 'subdir2', 'test.py'),
+                             '456')
 
 
             # testing glob-like patterns
@@ -339,6 +336,21 @@
                 shutil.rmtree(TESTFN, ignore_errors=True)
                 shutil.rmtree(TESTFN2, ignore_errors=True)
 
+    def test_copytree_special_func(self):
+
+        src_dir = self.mkdtemp()
+        dst_dir = os.path.join(self.mkdtemp(), 'destination')
+        self._write_data(os.path.join(src_dir, 'test.txt'), '123')
+        os.mkdir(os.path.join(src_dir, 'test_dir'))
+        self._write_data(os.path.join(src_dir, 'test_dir', 'test.txt'), '456')
+
+        copied = []
+        def _copy(src, dst):
+            copied.append((src, dst))
+
+        shutil.copytree(src_dir, dst_dir, copy_function=_copy)
+        self.assertEquals(len(copied), 2)
+
     @unittest.skipUnless(zlib, "requires zlib")
     def test_make_tarball(self):
         # creating something to tar
@@ -728,6 +740,7 @@
         finally:
             shutil.rmtree(TESTFN, ignore_errors=True)
 
+
 def test_main():
     support.run_unittest(TestShutil, TestMove)