code: def _get_mstd(cls, df, column, windows):
          
          window = cls.get_only_one_positive_int(windows)
          column_name = '{}_{}_mstd'.format(column, window)
          df[column_name] = df[column].rolling(min_periods=1, window=window,
                                               center=False).std()
docs: get moving standard deviation
  
          :param df: data
          :param column: column to calculate
          :param windows: collection of window of moving standard deviation
          :return: None