code: def execution_group(id):
      
      def add_execution_group(class_or_func):
          execution_groups = getattr(class_or_func, 'execution_groups', [])
          execution_groups.append(id)
          class_or_func.execution_groups = execution_groups
          return class_or_func
      return add_execution_group
docs: A decorator designed to be used with both classes and functions. Pass the 
      decorator some object that represents the Execution Group the decorated object 
      should be added to. If one test function in an Execution Group fails then no
      more tests from that Execution Group will run.