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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 exists(self):
 """ Test, if this task has been run. """

        try:
            self.es.get(index=self.marker_index, doc_type=self.marker_doc_type, id=self.marker_index_document_id())
            return True
        except elasticsearch.NotFoundError:
            logger.debug('Marker document not found.')
        except elasticsearch.ElasticsearchException as err:
            logger.warn(err)
        return False