code: def test_stack(tmpdir, runner):
      outputname = str(tmpdir.join("stacked.tif"))
      result = runner.invoke(
          main_group, ["stack", "tests/data/RGB.byte.tif", outputname]
      )
      assert result.exit_code == 0
      with rasterio.open(outputname) as out:
          assert out.count == 3
          assert out.read(1).max() > 0
  
file_path: rasterio/tests/test_rio_stack.py
imports: import rasterio
  from rasterio.rio.main import main_group
label_desc: Use image node_id 1 for calling a global function with example usage: test_stack(tmpdir, runner) without return types