code: def test_n_k_filter_defaults_custom(input, expected_output, params):
      out = n_k_filter(
          np.array(input),
          *params,
          forward_fill=True,
      )
      assert np.allclose(out, expected_output)
  
imports: import numpy
  import pytest
  from gluonts.nursery.anomaly_detection.filters import fill_forward, labels_filter, n_k_filter
label_desc: Use image node_id 3 for calling a global function with example usage: test_n_k_filter_defaults_custom(input, expected_output, params) without return types