Package patterns: how do they really work?

My project is in python, using poetry.

So far, my package is too big (> 300 Mb zipped!) and I went to investigate. I found in my sls zipped package files like:

skimage/morphology/tests/__pycache__/__init__.cpython-38.pyc

I’ve added to my serverless.yml, so far:

package:
  patterns:
    - '!node_modules/**' # by try-and-error I know this one work for sure and so others similar
    - '!test/**'
    - '!**/test*/**' # but, this one?
    - '!docs/**'
    - '!dist/**'
    - '!tools/**'
    - '!__pycache__/**'
    - '!**/__pycache__/**'
    - '!.mypy_cache/**'
    - '!integration_test/**'
    - '!my_pkg*/**'
    - '!*pytest_*'
    - '!*.pyc'

I really hoped at least - '!*.pyc' could work but, alas, no!

What patterns above do work, should work and definitely won’t work?

Could Serverless Framework Guide - AWS Lambda Guide - Packaging be improved?

Why not make use of a plain simple .ignore file? A property that could be added to the serverless.yml that, hopefully, wil work.

Could it be that package.patterns don’t work for the requirements?

Because I’ve cleaned $HOME/.cache/serverless-python-requirements/* and find-and-remove *.pyc, __pycache__ etc. and that seemed to have made a difference in my pkg size which is down to 100 Mb.

Last but not least. Serverless is a FANTASTIC stuff take tons out of ours shoulders when dealing with the horrible AWS services.