acloud: fix py3 compatible issue: NameError:  of name 'raw_input' is not defined

1 replace raw_input as six.moves.input.
2 replace __builtins__.raw_input as six.moves.input
3 replace __builtins__.open as six.moves.builtins.open.

BUG: 137195528
BUG: 144319256
Test: atest acloud_test --host &&
acloud-dev create &
acloud-dev setup &
acloud-dev reconnect &
acloud-dev setup

Change-Id: I1dd4e97a8c35e66639e7be8f5152f4713cd8fd35
diff --git a/internal/lib/utils_test.py b/internal/lib/utils_test.py
index 4b3cfe8..480b4d2 100644
--- a/internal/lib/utils_test.py
+++ b/internal/lib/utils_test.py
@@ -26,6 +26,7 @@
 
 import unittest
 import mock
+import six
 
 from acloud import errors
 from acloud.internal.lib import driver_test_lib
@@ -181,7 +182,7 @@
         mock_open = mock.mock_open(read_data=public_key)
         self.Patch(subprocess, "check_output")
         self.Patch(os, "rename")
-        with mock.patch("__builtin__.open", mock_open):
+        with mock.patch.object(six.moves.builtins, "open", mock_open):
             utils.CreateSshKeyPairIfNotExist(private_key, public_key)
         self.assertEqual(subprocess.check_output.call_count, 1)  #pylint: disable=no-member
         subprocess.check_output.assert_called_with(  #pylint: disable=no-member
@@ -252,7 +253,7 @@
                 mock.call(16)
             ])
 
-    @mock.patch("__builtin__.raw_input")
+    @mock.patch.object(six.moves, "input")
     def testGetAnswerFromList(self, mock_raw_input):
         """Test GetAnswerFromList."""
         answer_list = ["image1.zip", "image2.zip", "image3.zip"]