code: def test_boundless_vrt(path_rgb_byte_tif):
      with rasterio.open(path_rgb_byte_tif) as rgb:
          doc = rasterio.vrt._boundless_vrt_doc(rgb)
          assert doc.startswith("<VRTDataset")
          with rasterio.open(doc) as vrt:
              assert rgb.count == vrt.count
              assert rgb.dtypes == vrt.dtypes
              assert rgb.mask_flag_enums == vrt.mask_flag_enums
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_boundless_vrt(path_rgb_byte_tif) without return types