Rename buffer -> bytearray.
diff --git a/Lib/test/test_struct.py b/Lib/test/test_struct.py
index db6a97d..34596e0 100644
--- a/Lib/test/test_struct.py
+++ b/Lib/test/test_struct.py
@@ -560,11 +560,11 @@
     test_string = b'abcd01234'
     fmt = '4s'
     s = struct.Struct(fmt)
-    for cls in (buffer, bytes):
+    for cls in (bytes, bytearray):
         if verbose:
             print("test_unpack_from using", cls.__name__)
         data = cls(test_string)
-        if not isinstance(data, (buffer, bytes)):
+        if not isinstance(data, (bytes, bytearray)):
             bytes_data = bytes(data, 'latin1')
         else:
             bytes_data = data
@@ -575,7 +575,7 @@
             vereq(s.unpack_from(data, i), (bytes_data[i:i+4],))
         for i in range(6, len(test_string) + 1):
             simple_err(s.unpack_from, data, i)
-    for cls in (buffer, bytes):
+    for cls in (bytes, bytearray):
         data = cls(test_string)
         vereq(struct.unpack_from(fmt, data), (b'abcd',))
         vereq(struct.unpack_from(fmt, data, 2), (b'cd01',))