How to use the typeguard.TypeChecker function in typeguard

def test_nested(self):
        """Test that nesting of type checker context managers works as expected."""
        def foo(a: int):
            pass

        with warnings.catch_warnings(record=True):
            warnings.simplefilter('ignore', DeprecationWarning)
            parent = TypeChecker(__name__)
            child = TypeChecker(__name__)

        with parent, pytest.warns(TypeWarning) as record:
            foo('x')
            with child:
                foo('x')

        assert len(record) == 3

def checker(self):
        with warnings.catch_warnings():
            warnings.simplefilter('ignore', DeprecationWarning)
            return TypeChecker(__name__)

def checker(self):
        with warnings.catch_warnings():
            warnings.simplefilter('ignore', DeprecationWarning)
            return TypeChecker(__name__)

def test_nested(self):
        """Test that nesting of type checker context managers works as expected."""
        def foo(a: int):
            pass

        with warnings.catch_warnings(record=True):
            warnings.simplefilter('ignore', DeprecationWarning)
            parent = TypeChecker(__name__)
            child = TypeChecker(__name__)

        with parent, pytest.warns(TypeWarning) as record:
            foo('x')
            with child:
                foo('x')

        assert len(record) == 3

def init_typeguard() -> None:
    from typeguard import TypeChecker
    global tc
    tc = TypeChecker(check_mods)
    tc.start()