refactor to require argparse

setup.py

@@ -16,13 +16,10 @@ install_requires = [
           'WSGIUtils',
           'psutil>=0.2.0',
           'lxml',
-          'python-magic'
+          'python-magic',
+          'argparse'
           ]
 
-
-if sys.version_info < (2, 7):
-  install_requires.append('argparse')
-
 setup(name='cloudooo',
       version=version,
       description="XML-RPC document conversion server",