Creator function for creating an instance of a Docker image script.

def creator(entry, config):
        """Creator function for creating an instance of a Docker image script."""
        # writing Dockerfile
        dockerfile = render(config.script, model=config.model, env=config.env,
                            variables=config.variables, item=config.item)
        filename = "dockerfile.dry.run.see.comment"

        if not config.dry_run:
            temp = tempfile.NamedTemporaryFile(
                prefix="dockerfile-", mode='w+t', delete=False)
            temp.writelines(dockerfile)
            temp.close()
            filename = temp.name
            dockerfile = ''

        # rendering the Bash script for generating the Docker image
        name = entry['name'] + "-%s" % os.getpid() if entry['unique'] else entry['name']
        tag = render(entry['tag'], model=config.model, env=config.env, item=config.item)
        template_file = os.path.join(os.path.dirname(__file__), 'templates/docker-image.sh.j2')

        with open(template_file) as handle:
            template = handle.read()
            config.script = render(template, name=name, tag=tag,
                                   dockerfile_content=dockerfile,
                                   dockerfile_filename=filename)

        return Image(config)