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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_agent(self, entity_id):
 """Convert the entity dictionary into an INDRA Agent."""

        if entity_id is None:
            return None

        entity_info = self._entity_dict.get(entity_id)
        if entity_info is None:
            logger.warning("Entity key did not resolve to entity.")
            return None
        return get_agent_from_entity_info(entity_info)