docs: def format_dates(self, data, columns):
          """ This method translates columns values into datetime objects
  
          :param data: original Pandas dataframe
          :param columns: list of columns to cast the date to a datetime object
          :type data: pandas.DataFrame
          :type columns: list of strings
  
          :returns: Pandas dataframe with updated 'columns' with datetime objects
          :rtype: pandas.DataFrame
          """
  
          for column in columns:
              if column in data.columns:
                  data[column] = pandas.to_datetime(data[column])
  
          return data