docs: def Map(self, function):
          """Applies the function to every row in the table.
  
      Args:
        function: A function applied to each row.
  
      Returns:
        A new TextTable()
  
      Raises:
        TableError: When transform is not invalid row entry. The transform
                    must be compatible with Append().
      """
          new_table = self.__class__()
          # pylint: disable=protected-access
          new_table._table = [self.header]
          for row in self:
              filtered_row = function(row)
              if filtered_row:
                  new_table.Append(filtered_row)
          return new_table