docs: def reverse_transform(self, col):
          """Converts data back into original format.
  
          Args:
              col(pandas.DataFrame): Data to transform.
  
          Returns:
              pandas.DataFrame
          """
          if isinstance(col, pd.Series):
              col = col.to_frame()
  
          output = pd.DataFrame(index=col.index)
          output[self.col_name] = col.apply(self.safe_date, axis=1)
  
          return output