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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 timestamp(num_params, p_levels, k_choices, N):
 """ Returns a uniform timestamp with parameter values for file identification """

    string = "_v%s_l%s_gs%s_k%s_N%s_%s.txt" % (num_params,
                                               p_levels,
                                               k_choices,
                                               N,
                                               dt.strftime(dt.now(),
                                                           "%d%m%y%H%M%S"))
    return string