transport_as_context_manager.py

from contextlib import contextmanager


class Transport:
    @contextmanager
    def request(self, method, url, headers=None, stream=None):
        connection_closed = False

        def content():
            for chunk in [b"Hello", b", ", b"world", b"!"]:
                if connection_closed:
                    raise RuntimeError("Connection closed")
                yield chunk

        status_code = 200
        headers = {"Content-Length": "13"}
        stream = content()

        yield status_code, headers, stream

        connection_closed = True


class Response:
    def __init__(self, status_code, headers, stream):
        self.status_code = status_code
        self.headers = headers
        self.stream = stream

    def read(self):
        self.body = b''.join([chunk for chunk in self.stream])


class Client:
    def __init__(self):
        self.transport = Transport()

    def get(self, url, headers=None, stream=None):
        with self.transport.request("GET", url, headers, stream) as raw_resp:
            status_code, headers, stream = raw_resp
            response = Response(status_code, headers, stream)
            response.read()
        return response


client = Client()
response = client.get("https://www.example.org")
print(response.status_code, response.body)