new_contents: # -*- coding: utf-8 -*-
  import csv
  import os
  
  from collections import namedtuple
  
  
  class Inet():
      """Inet class"""
      def __init__(self, data_file=None):
          # Naive check for file type based on extension
          # First check filepath is passed as a parameter
          if data_file is not None:
              # Then split off the extension using os
              ext = os.path.splitext(data_file)[-1].lower()
              # then check ends with .csv or .json
              if ext == '.csv':
                  self.rows = []
                  with open(data_file) as f:
                      f_csv = csv.reader(f)
                      headings = next(f_csv)
                      Row = namedtuple('Row', headings)
                      for r in f_csv:
                          row = Row(*r)
                          self.rows.append(row)
              else:
                  raise TypeError("Input file must be of type .csv")
          else:
              raise AttributeError("No data_file path specified as a "
                                   "parameter to Inet object")
  
subject: Add read data file functionality to Inet class init