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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 _clean_dirty_objects(self):
 """ Clear all dirty attributes for the last object or list of objects successfully submitted to Zendesk. """

        if self._dirty_object is None:
            return
        if not is_iterable_but_not_string(self._dirty_object):
            self._dirty_object = [self._dirty_object]

        log.debug("Cleaning objects: {}".format(self._dirty_object))
        for o in self._dirty_object:
            if isinstance(o, BaseObject):
                o._clean_dirty()
        self._dirty_object = None