diff --git a/src/fix.py b/src/fix.py
index 4bac4c264..d198c4ce1 100644
--- a/src/fix.py
+++ b/src/fix.py
@@ -233,21 +233,22 @@ def ilen(iterator):
         i += 1
     return i
 
-## def group(seq, groupSize):
-##     L = []
-##     LL = []
-##     i = groupSize
-##     for elt in seq:
-##         if i > 0:
-##             LL.append(elt)
-##             i -= 1
-##         else:
-##             L.append(LL)
-##             i = groupSize
-##             LL = []
-##     if LL:
-##         L.append(LL)
-##     return L
+def group(seq, groupSize):
+    ret = []
+    L = []
+    i = groupSize
+    for elt in seq:
+        if i > 0:
+            L.append(elt)
+        else:
+            ret.append(L)
+            i = groupSize
+            L = []
+            L.append(elt)
+        i -= 1
+    if L:
+        ret.append(L)
+    return ret
 
 def itersplit(iterable, isSeparator, yieldEmpty=False):
     acc = []
diff --git a/test/test_fix.py b/test/test_fix.py
index c22a2aadd..703b9bd26 100644
--- a/test/test_fix.py
+++ b/test/test_fix.py
@@ -49,6 +49,13 @@ class FunctionsTest(unittest.TestCase):
         for elt in reviter([]):
             self.fail('reviter caused iteration over empty sequence')
 
+    def testGroup(self):
+        s = '1. d4 d5 2. Nf3 Nc6 3. e3 Nf6 4. Nc3 e6 5. Bd3 a6'
+        self.assertEqual(group(s.split(), 3)[:3],
+                         [['1.', 'd4', 'd5'],
+                          ['2.', 'Nf3', 'Nc6'],
+                          ['3.', 'e3', 'Nf6']])
+
     def testWindow(self):
         L = range(10)
         def wwindow(*args):