Build a C argument list from return type and arguments pairs.

def make_c_args(arg_pairs):
    """
    Build a C argument list from return type and arguments pairs.
    """
    logging.debug(arg_pairs)
    c_args = [
        '{} {}'.format(arg_type, arg_name) if arg_name else arg_type
        for dummy_number, arg_type, arg_name in sorted(arg_pairs)
    ]
    return ', '.join(c_args)