The argparse module provides an easy, declarative interface for creating 
command line tools, which knows how to: 
	parse the arguments and flags from sys.argv 
	convert arg strings into objects for your program 
	format and print informative help messages 
	and much more...
The argparse module improves on the standard library optparse module in a 
number of ways including: 
	handling positional arguments 
	supporting sub-commands 
	allowing alternative option prefixes like + and / 
	handling zero-or-more and one-or-more style arguments 
	producing more informative usage messages 
	providing a much simpler interface for custom types and actions

Module become part of standard library since python-2.7 
