code: def add_parameter(self, parameter: Parameter):
          
  
          # try reading the scenarios from the function arg or from the parameter attribute
          scenario_string = parameter.source_scenarios_string
          if scenario_string:
              _scenarios = [i.strip() for i in scenario_string.split(',')]
              self.fill_missing_attributes_from_default_parameter(parameter)
  
          else:
              _scenarios = [ParameterScenarioSet.default_scenario]
  
          for scenario in _scenarios:
              parameter.scenario = scenario
              self.parameter_sets[parameter.name][scenario] = parameter
  
          # record all tags for this parameter
          if parameter.tags:
              _tags = [i.strip() for i in parameter.tags.split(',')]
              for tag in _tags:
                  self.tags[tag][parameter.name].add(parameter)
docs: A parameter can have several scenarios. They are specified as a comma-separated list in a string.
          :param parameter:
          :return: