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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 update(self, resource, id_, updates):
 """Update document in index."""

        args = self._es_args(resource, refresh=True)
        if self._get_retry_on_conflict():
            args['retry_on_conflict'] = self._get_retry_on_conflict()

        updates.pop('_id', None)
        updates.pop('_type', None)
        self._update_parent_args(resource, args, updates)
        return self.elastic(resource).update(id=id_, body={'doc': updates}, **args)