Add __version__ and derive package version from it

Author: jpadilla

jwt/__init__.py

@@ -25,6 +25,7 @@
     basestring = str
 
 
+__version__ = '0.2.2'
 __all__ = ['encode', 'decode', 'DecodeError']
 
 

setup.py

@@ -1,14 +1,26 @@
 #!/usr/bin/env python
 import os
+import re
 from setuptools import setup
 
 
+def get_version(package):
+    """
+    Return package version as listed in `__version__` in `init.py`.
+    """
+    init_py = open(os.path.join(package, '__init__.py')).read()
+    return re.search("__version__ = ['\"]([^'\"]+)['\"]", init_py).group(1)
+
+
+version = get_version('jwt')
+
 with open(os.path.join(os.path.dirname(__file__), 'README.md')) as readme:
     long_description = readme.read()
 
+
 setup(
     name='PyJWT',
-    version='0.2.2',
+    version=version,
     author='Jeff Lindsay',
     author_email='progrium@gmail.com',
     description='JSON Web Token implementation in Python',