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From: rh <richard_hubbe11@lavabit.com>
Subject: Re: How does one make argparse print usage when no options are provided on the command line?
Date: Wed, 5 Dec 2012 12:52:12 -0800
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On Wed, 5 Dec 2012 11:31:57 -0700
Ian Kelly <ian.g.kelly@gmail.com> wrote:

> On Wed, Dec 5, 2012 at 9:48 AM, rh <richard_hubbe11@lavabit.com>
> wrote:
> > I have argparse working with one exception. I wanted the program to
> > print out usage when no command line options are given. But I only
> > came across other examples where people didn't use argparse but
> > instead printed out a separate usage statement. So they used
> > argparse for everything but the case where no command line args are
> > given.
> 
> if len(sys.argv) <= 1:
>     parser.print_usage()
>     sys.exit(1)
> else:
>     args = parser.parse_args()

Thanks.
It works in 2.7 and 3.3.