code: def ensembler(request):
      return Ensembler(
          normalizer=PValNormalizer(), aggregator=AverageAggregator()
      )
  
file_path: alibi-detect/alibi_detect/od/tests/test__knn/test__knn_backend.py
imports: import pytest
  import torch
  from alibi_detect.od.pytorch.knn import KNNTorch
  from alibi_detect.utils.pytorch.kernels import GaussianRBF
  from alibi_detect.od.pytorch.ensemble import Ensembler, PValNormalizer, AverageAggregator
  from alibi_detect.exceptions import NotFittedError, ThresholdNotInferredError
label_desc: Use image node_id 1 for calling a global function with example usage: ensembler(request) and returns: Ensembler