class_docstr: DataFile class for NCF. Iterator to read data from a csv file.
  Data must be sorted by user. Includes utilities for loading user data from
  file, formatting it and returning a Pandas dataframe.
class_docstr_tok: ["DataFile","class","for","NCF",".","Iterator","to","read","data","from","a","csv","file",".","Data","must","be","sorted","by","user",".","Includes","utilities","for","loading","user","data","from","file",",","formatting","it","and","returning","a","Pandas","dataframe","."]
code: def __exit__(self, *args):
      self.file.close()
      self.reader = None
      self.line_num = 0
      self.row, self.next_row = None, None
  
imports: import os
  from collections import OrderedDict
  import random
  import numpy
  import pandas
  import csv
  import logging
  from tqdm import tqdm
  from recommenders.utils.constants import DEFAULT_ITEM_COL, DEFAULT_USER_COL, DEFAULT_RATING_COL
label_desc: Use image node_id 7 for calling the DataFile obj's underlying member method code with example usage: obj.__exit__() without return types