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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 medium

How to Mock an Object Method in Python unittest

Mock a method on an instance or class with @patch.object, set its return value, and assert its call arguments in Python unittest.

unittest mock patch
Python 
import unittest
from unittest.mock import patch

class Calculator:
    def add(self, a, b):
        return a + b
    
    def multiply(self, a, b):
        return a * b

class TestCalculator(unittest.TestCase):
    def test_add_normal(self):
        calc = Calculator()
        result = calc.add(2, 3)
        self.asse…
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