code: def select(self):
      current_node = self
      while current_node.is_expanded:
          best_action = current_node.best_action()
          current_node = current_node.get_child(best_action)
      return current_node
  
imports: import collections
  import copy
  import math
  import numpy
label_desc: Use image node_id 9 for calling the Node obj's underlying member method code with example usage: obj.select() and returns: current_node