docstr: 创建一个新node，然后在该node中添加一个text_node，
  最后将node添加到root_node下
docstr_tok: ["\u521b\u5efa\u4e00\u4e2a\u65b0node\uff0c\u7136\u540e\u5728\u8be5node\u4e2d\u6dfb\u52a0\u4e00\u4e2atext_node\uff0c","\u6700\u540e\u5c06node\u6dfb\u52a0\u5230root_node\u4e0b"]
code: def create_text_node(self, node_name, node_value, root_node):
      """
      创建一个新node，然后在该node中添加一个text_node，
      最后将node添加到root_node下
      """
      new_node = self.doc.createElement(node_name)
      node_data = self.doc.createTextNode(node_value)
      new_node.appendChild(node_data)
      root_node.appendChild(new_node)
  
file_path: deep-learning-for-image-processing/others_project/trans_widerface_to_xml/create_xml.py
imports: import copy
  import os
  from xml.dom import minidom
label_desc: Use image node_id 3 for calling the XMLGenerator obj's underlying member method code with example usage: obj.create_text_node(node_name, node_value, root_node) without return types