Advanced usage question: How to call the pycodestyle with custom rule in the external file

I try to write a wrapper to call the pycodestyle with the rule in the wrapper file.

My rule/wrapper looks like.

import pycodestyle


def _main(**kwargs)


    @pycodestyle.register_check
    def image_lines(logical_line):
        r"""Find the line starting from the
        - FROM
        - image:
        directives.

        I801: def a():\n    pass\na()
        I802: def b():\n    pass\na()
        """ #noqa

        if logical_line.startswith('FROM'):
            yield 0, "I801 found the FROM directive"
        elif logical_line.startswith('image:'):
            yield 0, "I802 found the image directive"


    style = pycodestyle.StyleGuide(filename=['Dockerfile', 'docker-compose.yml'], select=['I801', 'I802'])

if __name__ == '__main__':
    _main()

Can you help me? Thank you.

Review the wrapper's _main function, @pycodestyle.register_check, and StyleGuide configuration. Reproduce the call against Dockerfile and docker-compose.yml, checking whether the selected I801 and I802 checks run. Done means the supported way to invoke a custom external rule is clearly documented or confirmed.