code: def login(ctx, host, scenario_name):  # pragma: no cover
      
      args = ctx.obj.get('args')
      subcommand = base._get_subcommand(__name__)
      command_args = {
          'subcommand': subcommand,
          'host': host,
      }
  
      s = scenarios.Scenarios(
          base.get_configs(args, command_args), scenario_name)
      for scenario in s.all:
          base.execute_subcommand(scenario.config, subcommand)
docs: Log in to one instance.