Return the parser object for this script.

def get_parser():
    """Return the parser object for this script."""
    from argparse import ArgumentParser, ArgumentDefaultsHelpFormatter
    from argparse import ArgumentTypeError

    def latitude(x):
        x = float(x)
        if x < -90.0 or x > 90.0:
            raise ArgumentTypeError("%r not in range [-90.0, 90.0]" % (x,))
        return x

    def longitude(x):
        x = float(x)
        if x < -180.0 or x > 180.0:
            raise ArgumentTypeError("%r not in range [-180.0, 180.0]" % (x,))
        return x

    parser = ArgumentParser(description=__doc__,
                            formatter_class=ArgumentDefaultsHelpFormatter)
    parser.add_argument("--lat",
                        dest="latitude",
                        required=True,
                        type=latitude,
                        help="Latitude (in -90, 90)")
    parser.add_argument("--lng",
                        dest="longitude",
                        required=True,
                        type=longitude,
                        help="Longitude (in -180, 180)")
    version = geocodertools.__version__
    parser.add_argument('--version',
                        action='version',
                        version=('geocodertools %s' % str(version)))
    return parser