code: def test_fillnodata_mask_ones(hole_in_ones):
      """when mask is all ones, image should be unmodified"""
      mask = np.ones((5, 5))
      result = fillnodata(hole_in_ones, mask)
      assert (hole_in_ones == result).all()
  
file_path: rasterio/tests/test_fillnodata.py
imports: import numpy
  import pytest
  from rasterio.fill import fillnodata
label_desc: Use image node_id 5 for calling a global function with example usage: test_fillnodata_mask_ones(hole_in_ones) without return types