code: def append_data(self, attribute, values):
          
          found = False
          if type(values) != list:
              values = [values]
          for col in self.Table:
              if attribute in col:
                  dict_values = [u"{0}".format(value) for value in values]
                  col[attribute] += dict_values
                  found = True
          if not found:
              raise KeyError(attribute)
docs: Appends the given value(s) to the attribute (column).