class_docstr: <<< WordCloud >>>
  
  Word cloud is to visually highlight the keywords that
  appear frequently in the text.
code: def _create_mask_image_variable(self, data: str) -> JsCode:
      image_str = self._encode_image_to_base64(image_or_path=data)
      if image_str is None:
          raise WordCloudMaskImageException(data=data)
      current_chart_id = self.chart_id
      self.add_js_funcs(
          f"""
          var maskImage_{current_chart_id} = new Image();
          maskImage_{current_chart_id}.src = '{image_str}';
          """
      )
      return JsCode(f"maskImage_{current_chart_id}")
  
file_path: pyecharts/pyecharts/charts/basic_charts/wordcloud.py
imports: import base64
  import random
  from pathlib import Path
  from ...None import options
  from ...None import types
  from ...charts.chart import Chart
  from ...commons.utils import JsCode
  from ...exceptions import WordCloudMaskImageException
  from ...globals import ChartType
label_desc: Use image node_id 2 for calling the WordCloud obj's underlying member method code with example usage: obj._create_mask_image_variable(data) and returns: JsCode