code: def test_warning_no():
      """No shadow warning is raised"""
      with rasterio.open("tests/data/RGB.byte.tif") as src:
          try:
              rm, gm, bm = src.read_masks()
          except NodataShadowWarning:
              pytest.fail("Unexpected NodataShadowWarning raised")
  
file_path: rasterio/tests/test_band_masks.py
imports: import numpy
  import pytest
  import rasterio
  from rasterio.enums import MaskFlags
  from rasterio.errors import NodataShadowWarning
label_desc: Use image node_id 6 for calling a global function with example usage: test_warning_no() without return types