code: def gen_experiment_ref(experiment_tag, n=10):
          
          experiment_id = gen_experiment_id(n=n)
          return '{0}_{1}'.format(experiment_tag, experiment_id)
docs: Generate a random string for naming.
  
          Parameters
          ----------
          experiment_tag : :obj:`str`
              tag to prefix name with
          n : int
              number of random chars to use
  
          Returns
          -------
          :obj:`str`
              string experiment ref