python-dependency-injector/examples/di_demo/example_no_di.py

import os


class ApiClient:

    def __init__(self):
        self.api_key = os.getenv('API_KEY')
        self.timeout = os.getenv('TIMEOUT')


class Service:

    def __init__(self):
        self.api_client = ApiClient()


if __name__ == '__main__':
    service = Service()