code: def _load_csv_file(csv_file):
          
          csv_content_list = []
  
          with io.open(csv_file, encoding='utf-8') as csvfile:
              reader = csv.DictReader(csvfile)
              for row in reader:
                  csv_content_list.append(row)
  
          return csv_content_list
docs: load csv file and check file content format
          @param
              csv_file: csv file path
              e.g. csv file content:
                  username,password
                  test1,111111
                  test2,222222
                  test3,333333
          @return
              list of parameter, each parameter is in dict format
              e.g.
              [
                  {'username': 'test1', 'password': '111111'},
                  {'username': 'test2', 'password': '222222'},
                  {'username': 'test3', 'password': '333333'}
              ]