Mock HTTP Calls Effortlessly in Python with responses

test_responses.py

import responses
import requests

@responses.activate
def test_not_found():
    responses.add(
        responses.GET,
        "https://api.example.com/user/42",
        json={"error": "not found"},
        status=404
    )

    resp = requests.get("https://api.example.com/user/42")
    assert resp.status_code == 404
    assert resp.json()["error"] == "not found"