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Testing & modern typing

pytest basics, mocks, type hints, TypedDict, Protocol, and static-checking patterns.

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Testing & modern typing easy

How to Mock return_value with MagicMock in Python unittest

Use unittest.mock.MagicMock to replace a dependency and set return_value to control what a mocked method returns during unit tests.

unittest mock magicmock
Python 
import unittest
from unittest.mock import MagicMock


class PaymentGateway:
    def charge(self, amount):
        raise NotImplementedError


class OrderService:
    def __init__(self, gateway):
        self.gateway = gateway

    def process_order(self, amount):
        return self.gateway.charge(amount)


class Test…
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