fix python2.7 encoding

Author: tigersk

setup.py

@@ -7,7 +7,7 @@
 from os import path
 from setuptools import find_packages, setup
 
-with open(path.join(path.abspath(path.dirname(__file__)), 'requirements.txt'), encoding='utf-8') as f:
+with open(path.join(path.abspath(path.dirname(__file__)), 'requirements.txt')) as f:
     install_requires = f.read()
 
 setup(