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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_outdated_docs( cls, app, env, added, changed, removed):
 # pragma: no cover """Handler for Sphinx's env-get-outdated event. This handler gives a Sphinx extension a chance to indicate that some set of documents are out of date and need to be re-rendered. The implementation here is stupid, for now, and always says that anything that uses the directive needs to be re-rendered. We should make it smarter, at some point, and have it figure out which modules are used by the associated handlers, and whether they have actually been updated since the last time the given document was rendered. """

        state = getattr(env, cls.directive_name, None)
        if state and state.doc_names:
            # This is stupid for now, and always says everything that uses
            # this autodoc generation needs to be updated. We should make this
            # smarter at some point and actually figure out what modules are
            # touched, and whether they have been changed.
            return sorted(state.doc_names)
        else:
            return []