when I use OS X system to write first tensorflow program,I get some error message, who can tell me how to fix it??

here is error message

bogon:~ ra$ python
Python 2.7.10 (default, Jul 14 2015, 19:46:27)
[GCC 4.2.1 Compatible Apple LLVM 6.0 (clang-600.0.39)] on darwin
Type "help", "copyright", "credits" or "license" for more information.

import tensorflow as tf
Traceback (most recent call last):
File "", line 1, in
File "/Library/Python/2.7/site-packages/tensorflow/init.py", line 4, in
from tensorflow.python import *
File "/Library/Python/2.7/site-packages/tensorflow/python/init.py", line 13, in
from tensorflow.core.framework.graph_pb2 import *
File "/Library/Python/2.7/site-packages/tensorflow/core/framework/graph_pb2.py", line 8, in
from google.protobuf import reflection as _reflection
File "/Library/Python/2.7/site-packages/google/protobuf/reflection.py", line 58, in
from google.protobuf.internal import python_message as message_impl
File "/Library/Python/2.7/site-packages/google/protobuf/internal/python_message.py", line 59, in
import six.moves.copyreg as copyreg
ImportError: No module named copyreg