Fail to install Python Wrapper

[huache]

When run pip install sentencepiece in python 3.6.1, I got this error:

  building '_sentencepiece' extension
  creating build/temp.linux-x86_64-3.6
  gcc -pthread -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -I/home/yuchang/miniconda3/include/python3.6m -c sentencepiece_wrap.cxx -o build/temp.linux-x86_64-3.6/sentencepiece_wrap.o -std=c++11 -g -O2 -I/usr/local/include
  cc1plus: warning: command line option ‘-Wstrict-prototypes’ is valid for C/ObjC but not for C++
  sentencepiece_wrap.cxx: In function ‘PyObject* _wrap_SentencePieceProcessor_Load(PyObject*, PyObject*)’:
  sentencepiece_wrap.cxx:3305:53: error: ‘PyString_AsStringAndSize’ was not declared in this scope
         PyString_AsStringAndSize(obj1, &str, &str_size);
                                                       ^
  sentencepiece_wrap.cxx: In function ‘PyObject* _wrap_SentencePieceProcessor_LoadOrDie(PyObject*, PyObject*)’:
  sentencepiece_wrap.cxx:3347:53: error: ‘PyString_AsStringAndSize’ was not declared in this scope
         PyString_AsStringAndSize(obj1, &str, &str_size);
                                                       ^

I googled the "PyString_AsStringAndSize", some one said that it means the code does not support python3 , so I change the python version to 2.7.12, then I got:

Collecting sentencepiece
  Using cached sentencepiece-0.0.0.tar.gz
    Complete output from command python setup.py egg_info:
    Package sentencepiece was not found in the pkg-config search path.
    Perhaps you should add the directory containing `sentencepiece.pc'
    to the PKG_CONFIG_PATH environment variable
    No package 'sentencepiece' found
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-build-joX_PJ/sentencepiece/setup.py", line 28, in <module>
        cmd('pkg-config sentencepiece --cflags'),
      File "/tmp/pip-build-joX_PJ/sentencepiece/setup.py", line 14, in cmd
        return os.popen(line).readlines()[0][:-1].split()
    IndexError: list index out of range
    
    ----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-joX_PJ/sentencepiece/

My OS is Ubuntu 16.04, python 3.6.1 installed by miniconda3 , python 2.7.12 installed with system.

Any advise or guidance would be greatly appreciated.

[huache]

My friend setup the python wrapper on Ubuntu 16.04 and python 2.7.12 successfully, so, it is certainly something wrong with my machine. But it is really wired.
Anyway, I should close this issue now, sorry to bother you.