class_docstr: prefix tree
docstr: get node representing given text
docstr_tok: ["get","node","representing","given","text"]
code: def getNode(self, text):
      "get node representing given text"
      node = self.root
      for c in text:
          if c in node.children:
              node = node.children[c]
          else:
              return None
      return node
  
file_path: calamari/calamari_ocr/thirdparty/ctcwordbeamsearch/PrefixTree.py
imports: from __future__ import division
  from __future__ import print_function
label_desc: Use image node_id 4 for calling the PrefixTree obj's underlying member method code with example usage: obj.getNode(text) and returns: node, None