code: def test_data_url():
      with Image(filename="rose:") as img:
          img.format = "PNG"
          data = img.data_url()
          assert data.startswith("data:image/png;base64,")
  
imports: import codecs
  import io
  import os
  import os.path
  import shutil
  import struct
  import sys
  import tempfile
  from pytest import mark, raises
  from wand.image import ClosedImageError, Image
  from wand.color import Color
  from wand.font import Font
label_desc: Use image node_id 46 for calling a global function with example usage: test_data_url() without return types