Testing DI enabled Python code.

test.py

import pytest
from unittest.mock import MagicMock

@pytest.fixture()
def patch_user_service():
    """
    reusable patcher, 
    handy when there are lots of test cases
    """
    user_connector = MagicMock()
    org_connector = MagicMock()
    service = UserService(user_connector, org_connector)
    return user_connector, org_connector

def test_get_user_with_org(patch_user_service):
    """
    test case that uses our patch_user_service
    we get access to the mocks can can check that they
    are called correctly etc.

    we could also alter their behavior before calling
    our service
    """
    m_user, m_org = patch_user_service

    result = service.get_user_with_org('test-ID')

    assert m_user.get_user.called
    assert m_org.get_org.called
    assert result
    assert 'user' in result
    assert 'org' in result