Python

Python 3.10 - parenthesized context managers

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Python 3.10 comes with support for continuation across multiple lines when using context managers.

An example👇

import unittest
from unittest import mock

from my_module import my_function


# Python < 3.10


class Test(unittest.TestCase):
    def test(self):
        with mock.patch("my_module.secrets.token_urlsafe") as a, mock.patch("my_module.string.capwords") as b, mock.patch("my_module.collections.defaultdict") as c:
            my_function()
            a.assert_called()
            b.assert_called()
            c.assert_called()

    def test_same(self):
        with mock.patch("my_module.secrets.token_urlsafe") as a:
            with mock.patch("my_module.string.capwords") as b:
                with mock.patch("my_module.collections.defaultdict") as c:
                    my_function()
                    a.assert_called()
                    b.assert_called()
                    c.assert_called()


# Python >= 3.10

class Test(unittest.TestCase):
    def test(self):
        with (
            mock.patch("my_module.secrets.token_urlsafe") as a,
            mock.patch("my_module.string.capwords") as b,
            mock.patch("my_module.collections.defaultdictl") as c,
        ):
            my_function()
            a.assert_called()
            b.assert_called()
            c.assert_called()