issue for pip install cryptography

when issue in 

Command "/home/andy/P_ENV1/env/bin/python3 -u -c "import setuptools, 

tokenize;__file__='/tmp/pip-build-kicuvik8/cryptography/setup.py';

exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 

'exec'))" install --record /tmp/pip-vebd4vda-record/install-record.txt 

--single-version-externally-managed --compile --install-headers 

/home/andy/P_ENV1/env/include/site/python3.5/cryptography" failed with error code 1 in 

/tmp/pip-build-kicuvik8/cryptography/

actually 

I am really the things going 

 solution ======**********************===========

sudo apt-get install build-essential libssl-dev libffi-dev python-dev

python

pip install -r requirement.txt



the requirement.txt looks likes:
=========================
ip==8.1.2
bumpversion==0.5.3
wheel==0.29.0
watchdog==0.8.3
flake8==2.6.0
tox==2.3.1
coverage==4.1
Sphinx==1.4.8
cryptography==1.4
PyYAML==3.11
click
requests
backtrader
=============================

git

~/.gitconfig

紀錄 local user 的相關資料及資訊

例如說 email 
           name


這些值 透過   git -global user.name=  "Andy" user.email= aaa@gmail.com


來設定 


to be continued