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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_id(n=10):
 """Generate a random string with n characters. Parameters n : int The length of the string to be generated. Returns ------- :obj:`str` A string with only alphabetic characters. """

    chrs = 'abcdefghijklmnopqrstuvwxyz'
    inds = np.random.randint(0,len(chrs), size=n)
    return ''.join([chrs[i] for i in inds])