def get_url(args):
    """Get the URL to use.

    Use a default URL if none is provided.

    Args:
        args (argparse.Namespace): The arguments given to ``spack create``

    Returns:
        str: The URL of the package
    """

    # Default URL
    url = 'https://www.example.com/example-1.2.3.tar.gz'

    if args.url:
        # Use a user-supplied URL if one is present
        url = args.url

    return url