# File lib/aws/simple_workflow/decision_task.rb, line 533
      def workflow_execution_opts options, workflow_execution

       if workflow_execution.is_a?(WorkflowExecution)
          options[:workflow_id] = workflow_execution.workflow_id
          options[:run_id] = workflow_execution.run_id
        elsif
          workflow_execution.is_a?(Hash) and
          workflow_execution[:workflow_id].is_a?(String) and
          workflow_execution[:run_id].is_a?(String) and
          workflow_execution.keys.length == 2
        then
          options.merge!(workflow_execution)
        elsif workflow_execution.is_a?(String)
          options[:workflow_id] = workflow_execution
        else
          msg = 'expected workflow_execution to be a WorkflowExecution ' +
            'object or workflow id or a hash with :workflow_id and :run_id'
          raise ArgumentError, msg
        end

      end