Method __take_sys_modules_snapshot

src/_pytest/pytester.py:743–753

(self)

        self._monkeypatch.undo()

    def __take_sys_modules_snapshot(self) -> SysModulesSnapshot:
        # Some zope modules used by twisted-related tests keep internal state
        # and can't be deleted; we had some trouble in the past with
        # `zope.interface` for example.
        #
        # Preserve readline due to https://bugs.python.org/issue41033.
        # pexpect issues a SIGWINCH.
        def preserve_module(name):
            return name.startswith(("zope", "readline"))

        return SysModulesSnapshot(preserve=preserve_module)

    def make_hook_recorder(self, pluginmanager: PytestPluginManager) -> HookRecorder:
        """Create a new :py:class:`HookRecorder` for a PluginManager."""