code: def review_metadata_csv(filedir, input_filepath):
      
      try:
          metadata = load_metadata_csv(input_filepath)
      except ValueError as e:
          print_error(e)
          return False
  
      with open(input_filepath) as f:
          csv_in = csv.reader(f)
          header = next(csv_in)
          n_headers = len(header)
          if header[0] == 'filename':
              res = review_metadata_csv_single_user(filedir, metadata,
                                                    csv_in, n_headers)
              return res
          if header[0] == 'project_member_id':
              res = review_metadata_csv_multi_user(filedir, metadata,
                                                   csv_in, n_headers)
              return res
docs: Check validity of metadata fields.
  
      :param filedir: This field is the filepath of the directory whose csv
          has to be made.
      :param outputfilepath: This field is the file path of the output csv.
      :param max_bytes: This field is the maximum file size to consider. Its
          default value is 128m.