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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def gen_experiment_ref(experiment_tag, n=10):
 """ 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 """

        experiment_id = gen_experiment_id(n=n)
        return '{0}_{1}'.format(experiment_tag, experiment_id)