code: def overwriteParam(self, row, param):
          
          if row == -1:
              row = self.nrows() - 1
          self._parameters[row] = param
docs: Assigns *param* to index *row*, overwritting the
          parameter at that location
  
          :param row: the ith parameter number
          :type row: int
          :param param: parameter to set
          :type param: dict