caffe2--------ImportError: No module named past.builtins

whale@sea:~/anaconda2/lib/python2.7/site-packages$ python
Python 2.7.14 |Anaconda custom (64-bit)| (default, Oct 16 2017, 17:29:19)
[GCC 7.2.0] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>>
>>> import  caffe2
>>> import  caffe2.python
>>> import  caffe2.python.core
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/caffe2/python/core.py", line 9, in <module>
    from past.builtins import basestring
ImportError: No module named past.builtins
>>> exit()
whale@sea:~/anaconda2/lib/python2.7/site-packages$ sudo  pip install future
The directory '/home/whale/.cache/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
The directory '/home/whale/.cache/pip' or its parent directory is not owned by the current user and caching wheels has been disabled. check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
Requirement already satisfied: future in /usr/local/lib/python2.7/dist-packages
whale@sea:~/anaconda2/lib/python2.7/site-packages$ pip  install   future
Collecting future
  Downloading future-0.16.0.tar.gz (824kB)
    100% |████████████████████████████████| 829kB 1.5MB/s
Building wheels for collected packages: future
  Running setup.py bdist_wheel for future ... done
  Stored in directory: /home/whale/.cache/pip/wheels/c2/50/7c/0d83b4baac4f63ff7a765bd16390d2ab43c93587fac9d6017a
Successfully built future
Installing collected packages: future
Successfully installed future-0.16.0
whale@sea:~/anaconda2/lib/python2.7/site-packages$ python -c 'from caffe2.python import core' 2>/dev/null && echo "Success" || echo "Failure"
Success
whale@sea:~/anaconda2/lib/python2.7/site-packages$ 

whale@sea:~/anaconda2/lib/python2./site-packages$ python
Python 2.7. |Anaconda custom (-bit)| (default, Oct  , ::)
[GCC 7.2.] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>>
>>> import  caffe2
>>> import  caffe2.python
>>> import  caffe2.python.core
Traceback (most recent call last):
  File "<stdin>", line , in <module>
  File "/usr/local/caffe2/python/core.py", line , in <module>
    from past.builtins import basestring
ImportError: No module named past.builtins
>>> exit()
whale@sea:~/anaconda2/lib/python2./site-packages$ sudo  pip install future
The directory '/home/whale/.cache/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
The directory '/home/whale/.cache/pip' or its parent directory is not owned by the current user and caching wheels has been disabled. check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
Requirement already satisfied: future in /usr/local/lib/python2./dist-packages
whale@sea:~/anaconda2/lib/python2./site-packages$ pip  install   future
Collecting future
  Downloading future-0.16..tar.gz (824kB)
    % |████████████████████████████████| 829kB .5MB/s
Building wheels for collected packages: future
  Running setup.py bdist_wheel for future ... done
  Stored in directory: /home/whale/.cache/pip/wheels/c2//7c/0d83b4baac4f63ff7a765bd16390d2ab43c93587fac9d6017a
Successfully built future
Installing collected packages: future
Successfully installed future-0.16.
whale@sea:~/anaconda2/lib/python2./site-packages$ python -c 'from caffe2.python import core' >/dev/null && echo "Success" || echo "Failure"
Success
whale@sea:~/anaconda2/lib/python2./site-packages$