docstr: Returns arr[start] + ... + arr[end]
docstr_tok: ["Returns","arr","[","start","]","+","...","+","arr","[","end","]"]
code: def sum(self, start=0, end=None):
      """Returns arr[start] + ... + arr[end]"""
      return super(SumSegmentTree, self).reduce(start, end)
  
imports: import argparse
  import operator
  import os
  import random
  import time
  import gym
  import matplotlib.pyplot
  import numpy
  import tensorflow
  import tensorlayer
label_desc: Use image node_id 2 for calling the SumSegmentTree obj's underlying member method code with example usage: obj.sum(start, end) and returns: super