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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 E_CMFR_N(t, N):
 """Calculate a dimensionless measure of the output tracer concentration from a spike input to a series of completely mixed flow reactors. :param t: The time(s) at which to calculate the effluent concentration. Time can be made dimensionless by dividing by the residence time of the CMFR. :type t: float or numpy.array :param N: The number of completely mixed flow reactors (CMFRS) in series. Must be greater than 1. :type N: int :return: Dimensionless measure of the output tracer concentration (concentration * volume of 1 CMFR) / (mass of tracer) :rtype: float :Examples: 0.7530643 0.9048374 """

    return (N**N)/special.gamma(N) * (t**(N-1))*np.exp(-N*t)