diff --git a/gitdb/pack.py b/gitdb/pack.py
index 115d943..2ad2324 100644
--- a/gitdb/pack.py
+++ b/gitdb/pack.py
@@ -410,7 +410,7 @@ def offsets(self):
         if self._version == 2:
             # read stream to array, convert to tuple
             a = array.array('I')    # 4 byte unsigned int, long are 8 byte on 64 bit it appears
-            a.fromstring(buffer(self._cursor.map(), self._pack_offset, self._pack_64_offset - self._pack_offset))
+            a.frombytes(buffer(self._cursor.map(), self._pack_offset, self._pack_64_offset - self._pack_offset))
 
             # networkbyteorder to something array likes more
             if sys.byteorder == 'little':
diff --git a/gitdb/test/lib.py b/gitdb/test/lib.py
index ab1842d..42b9ddc 100644
--- a/gitdb/test/lib.py
+++ b/gitdb/test/lib.py
@@ -157,7 +157,7 @@ def make_bytes(size_in_bytes, randomize=False):
         random.shuffle(producer)
     # END randomize
     a = array('i', producer)
-    return a.tostring()
+    return a.tobytes()
 
 
 def make_object(type, data):